The aim of this study was to investigate the effects of human lactoferrin (hLf) in mice exposed to acute sublethal gamma-irradiation. C57Вl/6 male mice were used for the experiments. Animals from experimental groups were exposed to whole-body gamma-radiation at a dose of 7.5 Gy. Some animals received an intraperitoneal injection of lactoferrin (Lf) immediately and then at 24 hours after the irradiation. The effect of Lf on survival rate and life span was studied. Changes in the physiological parameters were evaluated by laser correlation spectroscopy of blood serum, histological examination of the liver, and blood leukocyte shift index count on day 30 after irradiation. The Lf administration increased the survival rate and life span of irradiated mice during the experiment. In addition, Lf had a compensatory effect on the white blood formula, serum composition and liver condition of irradiated animals.

The purpose of our study was to search for possible changes in the parameters of the cardiovascular system in adolescents during the period from 2004 to 2020 against the background of the introduction of digital technologies into the educational environment. Methods: A comparative analysis of the parameters of the cardiovascular system in female and male adolescents aged from 13.9 to 15.4 years was carried out (57 adolescents in 2004 and 53 adolescents in 2020). We used a spiroartheriocardiorythmograph allowing recording of heart rate (HR) and blood pressure (BP) and spectral parameters of HR variability and variability of systolic (sBP) and diastolic (dBP) BP. The parameters were recorded at rest in the sitting position for over two min. All studies were performed during school hours in February-March. Results: An increase in the mean sBP values and an increase in the proportion of adolescents with BP in the "hypertension" range to 55% were found in 2020. The total power of HR variability spectrum remained constant, while the relative power of the LF range increased and the absolute power of the VLF range tended to decrease. In the sBP variability spectrum, an increase in the total power and all its ranges was detected, but the relative power of the LF range decreased. In the dBP variability spectrum, the absolute power of the VLF range decreased, while the total power remained constant. No changes in the stress index and alpha index were detected.The dynamics of the parameters in male and female adolescents were similar. Conclusion: These findings indicate significant shifts in the parameters of the cardiovascular system in adolescents from 2004 to 2020 recorded during school hours analysis of the parameters of heart rate and BP variability reflecting the mechanisms of regulation of the cardiovascular system, suggests that the identified shifts were caused by psycho-emotional stress. We associate this state with the use of digital educational technologies. This trend requires the close attention of school health professionals. It would be expedient to establish the practice of BP measurements at school and share hygienic recommendations on working with digital technologies for students and their parents.