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The impact of ionizing radiation on genetic change is well established, yet the extent to which naturally occurring radiation fields have influenced evolutionary trajectories remains incompletely understood. This study examined correlations between microbial evolution and the radiation and geochemical environments associated with natural fission reactors, with emphasis on the Oklo–Bangombé system in present-day Gabon, Africa. The current paper compares plausible doserate regimes adjacent to reactor zones with published observations of radiationinduced phenotypes, geneexpression changes, and repair strategies in model organisms and complex biotas. This study further considers indirect mechanisms (e.g., water radiolysis, redox restructuring, tracemetal mobilization) by which natural reactors could have modulated ecological selection pressures over long timescales. The synthesis supports the plausibility of three interacting pathways: (i) increased mutation supply under low, chronic dose rates; (ii) selection in oxidantrich, redoxstratified niches; and (iii) metabolic subsidies (e.g., H₂) from radiolysis that support chemotrophic guilds. Although temporal–spatial associations exist between reactor activity and biological innovations preserved in Paleoproterozoic strata of Gabon, current evidence remains correlational rather than demonstrably causal. The study further outlines testable predictions and experimental designs capable of discriminating among these mechanisms.
Melanoma is considered to be a very aggressive cancer due to its rapid growth, early and multiple metastases and limited response to standard treatment. Many researchers have hypothesized that the combination of radiation therapy and immunotherapy in the treatment of melanoma primary tumors and metastases improves the efficiency of these methods as compared to their use separately. Therefore, combined therapy is an increasingly popular topic in radiation oncology. Although the mechanism of immune response to ionizing radiation remains unclear, known are the factors involved in the immune response, including NK and CD8(+) T cells. Many studies have demonstrated the importance of inflammatory factors, primarily cytokines, in the response to ionizing radiation. In turn, many cytokines released in an irradiated organ, such as tumor necrosis factor α (TNFα), interleukins IL1 and IL6 and transforming growth factor beta (TGFβ), can induce the production of significant amounts of reactive oxygen species that are associated with the induction of DNA damage in tumor cells. In relation to anticancer immunotherapy, the clinical data obtained to date can encourage future studies combining radiation therapy and the inhibitors of cell division checkpoints in the treatment of advanced melanoma. In a recent study, melanoma cell lines became more sensitive to radiation after BRAF inhibition, which provides a potential synergistic mechanism of BRAF inhibitor (BRAFi) combined with radiation therapy for better effects of treatment. In this article, we present a systematic review of the literature on the use of the combination of radiation therapy and immunotherapy in the treatment of melanoma.