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The comet assay or single cell gel electrophoresis, is the most common method used to measure strand breaks and a variety of other DNA lesions in human populations. To estimate the risk of overall mortality, mortality by cause, and cancer incidence associated to DNA damage, a cohort of 2,403 healthy individuals (25,978 person-years) screened in 16 laboratories using the comet assay between 1996 and 2016 was followed-up. Kaplan-Meier analysis indicated a worse overall survival in the medium and high tertile of DNA damage (p < 0.001). The effect of DNA damage on survival was modelled according to Cox proportional hazard regression model. The adjusted hazard ratio (HR) was 1.42 (1.06-1.90) for overall mortality, and 1.94 (1.04-3.59) for diseases of the circulatory system in subjects with the highest tertile of DNA damage. The findings of this study provide epidemiological evidence encouraging the implementation of the comet assay in preventive strategies for non-communicable diseases., (© 2021. The Author(s).)

The alkaline comet assay, or single cell gel electrophoresis, is one of the most popular methods for assessing DNA damage in human population. One of the open issues concerning this assay is the identification of those factors that can explain the large inter-individual and inter-laboratory variation. International collaborative initiatives such as the hCOMET project - a COST Action launched in 2016 - represent a valuable tool to meet this challenge. The aims of hCOMET were to establish reference values for the level of DNA damage in humans, to investigate the effect of host factors, lifestyle and exposure to genotoxic agents, and to compare different sources of assay variability. A database of 19,320 subjects was generated, pooling data from 105 studies run by 44 laboratories in 26 countries between 1999 and 2019. A mixed random effect log-linear model, in parallel with a classic meta-analysis, was applied to take into account the extensive heterogeneity of data, due to descriptor, specimen and protocol variability. As a result of this analysis interquartile intervals of DNA strand breaks (which includes alkali-labile sites) were reported for tail intensity, tail length, and tail moment (comet assay descriptors). A small variation by age was reported in some datasets, suggesting higher DNA damage in oldest age-classes, while no effect could be shown for sex or smoking habit, although the lack of data on heavy smokers has still to be considered. Finally, highly significant differences in DNA damage were found for most exposures investigated in specific studies. In conclusion, these data, which confirm that DNA damage measured by the comet assay is an excellent biomarker of exposure in several conditions, may contribute to improving the quality of study design and to the standardization of results of the comet assay in human populations., Competing Interests: Declaration of Competing Interest The authors report no declarations of interest., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Purpose of the Study: Examine the dynamics of the content of ferritin and other indicators of iron metabolism in the blood of patients with colorectal cancer before surgery and in the postoperative period to 7 days, and compare it with other known non-specific criteria of the acute phase of inflammation. Respond to the question whether changes in iron metabolism parameters in patients with colorectal cancer after surgery are specific., Materials and Methods: The content of ferritin, transferrin, iron and unsaturated iron binding capacity (TIBE) in the blood serurii of patients with coidrecral cancer before surgery and in the postoperative period of 1, 3 and 7 days was determined at the biochemical analyzer Cobas Integra 400. The values of parameters in the group of individuals without cancer pathology (control group) were used for comparison., Results: Before surgery, patients studied parameters were within normal limits. In the postoperative period (7 days) ferritin level was significantly increased by 88%, and transferrin level was reduced by 73% in relation to that of the control group (p <0.05; U-Mann-Whitney). Total iron binding capacity was significantly reduced by 250%., Conclusions: Opposite changes of ferritin and transferrin, known as the acute-phase proteins, show predominance in the first week after surgery nonspecific reaction of patients to surgical stress. These metalioproteins are considered as one of the markers of the stress. We compared revealed changes in the studied parameters of iron system with the experimental data on the changes in the membrane potential of red blood cells and lymphocytes, and came to the conclusion that the identified synchronicity indicates their potential conditionality.

The effects of copper nanoparticles on the structure and function of the immune system organs (thymus and spleen) and intensity of free radical processes in the spleens of rats with sarcoma 45 were studied. A relationship between morphological and biochemical changes and antitumor efficiency of copper nanoparticles was demonstrated.