Problemy radiatsiinoi medytsyny ta radiobiolohii最新文献

The impact of the environment on human health in modern conditions cannot be underestimated. The study of thepathogenesis of disease is impossible without establishing the factors of destabilization of biological membranes.The article highlighted the problem of lipid peroxidation and antioxidant defense associated with the accumulationof radiocesium in the placenta.

Objective: to determine the biochemical markers of miscarriage associated with the accumulation of 137Cs in the placenta.

Materials and methods: According to the research design, pregnant women were divided into groups. Group 1included 153 women with reproductive losses in anamnesis and signs of termination of the current pregnancy.Group 2 (control) included 30 women with an uncomplicated pregnancy and medical history. The women of Group1 were divided into subgroups: 1a - in which the pregnancy ended with timely delivery, despite threatening signsof termination; 1b - pregnancy ended in late premature birth; 1c - pregnancy ended in early premature birth.Accumulation of 137Cs with different activity was detected in the placentas of both groups by β-spectrometry. Theeffect of 137Cs is the activation of free radical processes. The strength of oxidative stress was studied by the contentof diene conjugates (DC) and malondialdehyde (MDA) in the blood. The antioxidant capacity was determined by theactivity of catalase, glutathione-S-transferase, and superoxide dismutase (SOD). Biochemical studies were performed using a spectrophotometer «Specol-11» (Germany).

Results: The increase of DC in the 1st trimester by 2.25 times, in the 2nd and 3rd trimesters by 1.25 and 1.5 times indicates the activation of free radical reactions. The trigger for late preterm births is an increase in MDA in the 1sttrimester by 17.4 %. An increase in MDA by 23.4 % in the 1st trimester indicates the risk of early premature birth andintrauterine death of the fetus. A decrease in the activity of SOD in the 1st trimester by 13.0 % can be a predictor ofpremature birth. Decreased activity of SOD by 18.2 % in the 1st trimester indicates decompensation of adaptationmechanisms. As a result of oxidative stress caused by the accumulation of 137Cs in the placenta, the activity of GSTdecreases almost 2 times. In the 1st trimester, catalase activity in the blood of pregnant women of the 1b and 1csubgroups was reduced by 39.2 % and 44.9 %. The dynamics of catalase in the 2nd trimester indicate the activationof adaptive reactions. After 25 weeks, catalase activity is inhibited in pregnant women of subgroups 1b and 1c dueto depletion of antioxidant protection mechanisms. The activity of 137Cs in the placenta above 4.5 Bq/kg causesdepletion of antioxidant mechanisms, which is confirmed by persistent inhibition of catalase and SOD activityagainst the background of high levels of DC and MDA in the blood. Critical for pregnancy is the activity of 137Cs inthe place

The introduction of new radiation technologies in modern radiotherapy of cancer patients is still in some cases associated with the risk of developing early and distant complications in healthy tissues surrounding the tumour. The causes of their occurrence, pathogenesis and radiobiological characteristics are reviewed and briefly described. The rate of the manifestation of complications depends on the radiosensitivity of tissues and is determined by the amount of absorbed dose of ionizing radiation. In contrast to early complications, the development of distant radiation effects is irreversible and progressive. The features of early radiation complications are considered on the example of patients with gynaecological oncology, the incidence of which has been rapidly increasing in recent years. The interest of researchers in this pathology is due to the danger of developing complications from critical pelvic organs. Attention is focused on determining the individual radiosensitivity of the patients' body using the chromosomal G2 test to predict the development of post-radiation complications. The paper advocates for the necessity of developing nontoxic radioprotectors that would show affinity only to healthy tissues, would not require additional concomitant therapy and would definitely improve the quality of life of patients.

Objective: Evaluation of structural features and metabolic/biochemical abnormalities of the bone tissue and relevant regulation patterns in children, residing in the radiologically contaminated territories (RCT).

Materials and methods: Children (n = 148) aged 7 to 18 years old were involved in the study. Bone mineral density (BMD) is given in 3 grades according to the mean square deviation values, namely Grade I - standard (n = 75),Grade II - reduced (n = 45) and Grade III - very low one (n = 28). Cholelithiasis, urolithiasis, cancer and endocrinediseases, as well as bone fractures in the family members of children were taken into account. Bone fractures in thehistory and jaw anomalies were evaluated in study participants. A spectrum of blood biochemical parameters, namely the serum content of total protein, alkaline phosphatase (APh), serum iron (SI), creatinine, calcium, vitamin D,parathyroid hormone, calcitonin, pituitary thyroid stimulating hormone (TSH), free thyroxine (FT4), and cortisolboth with urine content of amino acids were assayed. Radiation doses in study participants were calculated.

Results: Abnormalities of the bone organic component were diagnosed according to the reduced serum level of creatinine, decreased urine levels of glycine and lysine, and increased urine content of oxyproline. A direct relationshipwas established between the urine level of oxyproline and serum TSH content (r = 0.42; p < 0.05). Abnormalities inthe bone mineral component were accompanied by calcium deficiency, increased serum content of APh anddecreased BMD. A direct relationship was established between the serum levels of calcium and APh (r = 0.33) andan inverse one between the APh serum content and BMD (r = -0.60) (р < 0.05). An inverse relationships were established between the serum vitamin D content and APh activity (r = -0.34), between the serum levels of vitamin D andSI (r = -0.35) (р < 0.05). Incidence and patterns of the abnormal parameters depending on BMD grades were established. Biochemical parameters reflecting the state of bone organic and mineral components both with the level ofserum iron and hormonal regulation of bone formation were ranked. Individual radiation doses of children were(0.66 ∓ 0.04) mSv being not correlated with any other studied parameters.

Conclusions: Evaluation of the structural and functional components of bone tissue sheds light on the mechanismsof bone formation processes, metabolism of biochemical cascade, and regulatory pathways aiming the timely correction of abnormalities.

Objective: To establish the level of chromosomal instability in human peripheral blood lymphocytes during thedevelopment of secondary radiation-induced bystander effect.

Materials and methods: Human peripheral blood lymphocytes; culture of human non-small-cell lung cancer cell lineA549 (irradiated in vitro by 137Cs in a dose of 0.50 Gy/unirradiated). Cytogenetic analysis of uniformly colored chromosomes of human peripheral blood lymphocytes with determination of the frequency of all types of aberrations.

Results: The mean group frequency of chromosome aberrations (4.75 per 100 cells) in human peripheral blood lymphocytes co-cultivated with conditioned culture medium from bystander cells of human non-small cell lung cancercell lines A-549 exceeded the control (1.60 per 100 cells) (p < 0.001) due to an increase in the frequency of singlefragments from 1.20 to 3.95 per 100 cells (p < 0.001). The mean group frequency of chromosome aberrations andchromatid-type aberrations in human peripheral blood lymphocytes during the development of primary (5.80 and4.35 per 100 cells, respectively) and secondary (4.75 and 3.95 per 100 cells, respectively) radiation-induced bystander effect did not significantly differ from each other (p > 0.05).

Conclusions: Under the conditions of co-cultivation of human peripheral blood lymphocytes with conditioned culture medium from bystander cells of human non-small cell lung cancer A-549, a secondary radiation-induced bystander effect was registered, the cytogenetic manifestation of which was an increase in the level of chromosomalinstability due to the rise in the frequency of chromatid-type aberrations (single fragments). The levels of chromatid-type chromosome aberrations during the development of the primary and secondary radiation-inducedbystander effect did not differ significantly. The development of the secondary radiation-induced bystander effectdid not affect the induction of chromosomal-type aberrations.

The WHO educational module УДК «Ma naging exposure assessment and medical response to a radiation emergency in Ukraine» was developed and implemented. In total, 25 trainings were conducted for 377 healthcare professionals from 6 regions of Ukraine during 2023-2024.

Research activities and scientific advance achieved in 2023 at the State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» (NRCRM) concerning medical problems of the Chornobyl disaster, radiation medicine, radiobiology, radiation hygiene and epidemiology in collaboration with the WHO network of medical preparedness and assistance in radiation accidents are outlined in the annual report. The report presents the results of fundamental and applied research works of the study of radiation effects and health effects of the Chornobyl accident. The institution has been reorganized and since December 2023 has been called the State Institution «National Research Center for Radiation Medicine, Hematology and Oncology» (NRCRM). The report also shows the results of scientificorganizational and health care work, staff training. The Scientific Council meeting of NAMS approved the NRCRM Annual Report.

The review is devoted to the use of a new class of radiopharmaceuticals (RPs) - chemokine receptor ligands - in oncological practice. The chemokine receptor CXCR4 is of particular interest as a molecular target in the diagnosis and treatment of malignant tumors, as it plays an important role in carcinogenesis. By interacting with the chemokine CCXL12, it activates cell signaling pathways that affect tumor cell proliferation, angiogenesis, metastasis growth, and apoptosis inhibition. The CXCR4 receptor is overexpressed on the cell surfaces of many hematological malignancies and solid tumors, the expression is correlated with poor prognosis. Numerous inhibitors of the CXCR4/CXCL12 axis and their radionuclide-labeled analogues have been developed, which allow visualization of CXCR4 and radioligand therapy. The possibilities of using RP 68Ga-Pentixafor for the diagnosis of hemoblastosis and solid tumors are shown. The therapeutic RP 177Lu/90Y-Pentixather was tested in the complex treatment of spread hemoblastoses and showed the direct antitumor activity and the desired myeloablative effect. Taking into account the results already obtained and the importance of new therapeutic approaches, especially in the field of refractory spread malignancies, it is obvious that these studies will be further developed.

Under the conditions of a full-scale russian invasion of Ukraine, the danger of the development of radiation and nuclear emergency situations in the region has increased significantly. An external independent assessment of the ability of health care system of the Republic of Moldova to respond to emergency situations revealed the need to develop a training program for medical workers on the basics of responding to radiation and nuclear threats. In addition, the evaluation recommended the development of a standard for victims care taking into account the existing evidence base.