Analysis of the epidemic situation of the COVID-19 coronavirus infection in Ukraine.

The epidemic process of COVID-19 in the world developed rapidly. The situation with morbidity, despite the establishment of quarantine, the introduction of restrictive anti-epidemic measures, and vaccination, remains difficult. The results of research on the influence of meteorological factors on the dynamics of the incidence of COVID-19, hospitalization, and mortality are ambiguous and contradictory. The purpose of this study is to analyze the indicators of morbidity, hospitalization, and mortality from COVID-19 in Ukraine, and to establish the level of influence of meteorological factors on them. A high variation in morbidity, hospitalization, and mortality rates was observed in Ukraine, in 2020-2021. A total of 3 waves of disease growth were established. The curve of hospitalization indicators of patients with COVID-19 had a correlation dependence on the incidence curve r = 0.766 (р <0.05), the maximum rates of hospitalization and mortality were registered in September-December 2021. A direct strong correlation was established between the frequency of registration of cases of COVID-19 and mortality - r = 0.899 (р <0.05). Most cases of COVID-19 were registered in the cold season, the least in June-August. Inverse correlations of moderate strength were established between the indicators of morbidity, hospitalization, and mortality and air temperature levels (-0.370< r <-0.461). Direct correlations of average strength (0.538< r <0.632) were established with the levels of relative air humidity.

Incidence and risk factors of salmonellosis in Ukraine.

The article, based on the reports of the Ministry of Health of Ukraine, presents the materials of the epidemiological surveillance of salmonellosis in 2011-2018. To assess the influence of factors on the epidemic process of salmonellosis, the demographic situation, income and living conditions of the population were studied; average monthly air temperature, relative humidity, precipitation; the quantitative and qualitative composition of the microbiocenosis of patients with signs of acute intestinal infection. It was found that in Ukraine the incidence of salmonellosis is high. Outbreaks of salmonellosis are recorded. S. enteritidis is most often isolated from the clinical material of patients, carriers and human objects (p <0.05). The risk groups for salmonellosis are children (p <0.05), as well as the rural population (p 7lt;0.05). The low level of sanitary and epidemiological control at the stages of production, transportation and sale of food products, water supply contributes to the spread of salmonellosis. Natural factors have a regulating effect on the intensity of the epidemic salmonella process: a strong direct relationship is established between the incidence and air temperature and precipitation (p <0.05). Salmonella enters into a competitive or synergistic relationship with other microorganisms in the intestinal biotope. Thus, the intensity of the epidemic process of salmonellosis can be influenced not only by external (natural and social), but also by internal factors.

Expression of mRNA coding for TGF-beta and its receptors in irradiated human breast carcinoma MCF-7 cells differing in their sensitivity to doxorubicin.

AIM: The effect of X-irradiation on the expression of mRNAs coding for transforming growth factor beta (TGF-beta) and its receptors was compared in human breast carcinoma MCF-7 cells differing in their sensitivity to doxorubicin. METHODS: Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the estimation of mRNAs expression for TGF-beta1, TGF-beta2 and TGF-beta type I and II receptors in the unirradiated and irradiated cells of two sublines of MCF-7 cells--sensitive (MCF-7(wt)) and resistant (MCF-7(DOX/R)) to doxorubicin. RESULTS: X-irradiation caused an increase in TGF-beta1 coding for mRNA expression in both breast cancer cell lines tested and an elevation of TGF-beta2 mRNA expression in doxorubicin-resistant subline. The down-regulation of TGF-beta type I and II receptors in the irradiated MCF-7(DOX/R) cells was revealed at the transcriptional level. CONCLUSIONS: The results of our study show that the development of refractoriness of used tumor cells to anti-cancer drug doxorubicin, at least partly, can be caused by the impairment in TGF-beta signaling pathway.

Comparative study of human breast carcinoma MCF-7 cells differing in their resistance to doxorubicin: effect of ionizing radiation on apoptosis and TGF-beta production.

AIM: The aim of the study was to investigate the survival and growth of human breast carcinoma MCF-7 cells with different sensitivity to doxorubicin and production of transforming growth factor beta-(TGF-beta) in dependence on the dose- and duration of X-ray in order to check if the cross-resistance to doxorubicin and radiation effects exists. METHODS: Determination of cell number and valiability using trypan blue (0.1% (w/v)) exclusion method, Western blot analysis of p53 protein expression, biological testing of TGF-beta activity, lectinocytochemical analysis for apoptosis quantitative estimation in unirradiated and irradiated cells of both sublines of MCF-7 cells--sensitive (MCF-7(wt)) and resistant (MCF-7(DOX/R)) to doxorubicin. RESULTS: It was found that doxorubicin-resistant breast cancer cells were also more refractory to X-radiation-dependent growth inhibition. There were revealed different effects of distinct doses of X-ray on p53 protein expression by cells of both sublines. The level of production of TGF-beta was compared in non-irradiated MCF-7 cells and in these cells exposed to X-radiation. It was shown that X-radiation increased TGF-beta activity in the conditioned medium of the irradiated cells of both doxorubicin-sensitive and -resistant lines. CONCLUSIONS: The results of our study suggest that the biological effects of X-radiation on human breast cancer MCF-7 cells can be at least partly mediated by TGF-beta. Taking into account that TGF-beta is a potent natural immunosupressor, one may consider that an increased activity of this cytokine can intensify negative effects of X-radiation.