Radiation-induced bystander effects refer to the induction of biological changes in cells not directly hit by radiation implying that the number of cells affected by radiation is larger than the actual number of irradiated cells. Recent in vitro studies suggest the role of extracellular vesicles (EVs) in mediating radiation-induced bystander signals, but in vivo investigations are still lacking...

Ionizing radiation has been proved a major stress that can induce carcinogenesis. Nuclear DNA is the main target of ionizing radiation, exposure of which is followed by many types of DNA damages. DNA double-strand breaks (DSBs) induced by ionizing radiation are considered the most relevant lesion for mutations and carcinogenesis, and unrepaired or misrepaired DSBs are a serious threat to genomi...

Much research in social psychology has shown that otherwise helpful people often fail to help when bystanders are present. Research in developmental psychology has shown that even very young children help and that the presence of others can actually increase helping in some cases. In the current study, in contrast, 5-year-old children helped an experimenter at very high levels when they were al...

Exposure of GM10115 hamster-human hybrid cells to X-rays can result in the induction of chromosomal instability in the progeny of surviving cells. This instability manifests as the dynamic production of novel sub-populations of cells with unique cytogenetic rearrangements involving the "marker" human chromosome. We have used the comet assay to investigate whether there was an elevated level of ...

Although radiation carcinogenesis has been shown both experimentally and epidemiologically, the use of ionizing radiation is also one of the major modalities in cancer treatment. Various known cellular and molecular events are involved in carcinogenesis. Apart from the known phenomena, there could be implications for carcinogenesis and cancer prevention due to other biological processes such as...

Prior work has provided incremental phases to a microdosimetry modeling program to describe the dose response behavior of the radio-protective adaptive response effect. We have here consolidated these prior works (Leonard 2000, 2005, 2007a, 2007b, 2007c) to provide a composite, comprehensive Microdose Model that is also herein modified to include the bystander effect. The nomenclature for the m...

We report data demonstrating that zebrafish embryos irradiated by α-particles can release a stress signal into the water, which can be communicated to the unirradiated zebrafish embryos sharing the same water medium, and then these unirradiated zebrafish embryos can release a feedback stress signal back to the irradiated embryos. The effects of radiation on the whole embryos were studied throug...