When ionizing radiation passes through a material it imparts some of its energy to that material. The imparted energy may be high enough to cause a break in bonds inside the molecules or between molecules or both, in such cases, free radicals are created. The type, lifetime, extent, fate and origin of those free radicals may differ according to several factors; most of them are beyond the subje...

BACKGROUND Melanin pigments are ubiquitous in nature. Melanized microorganisms are often the dominating species in certain extreme environments, such as soils contaminated with radionuclides, suggesting that the presence of melanin is beneficial in their life cycle. We hypothesized that ionizing radiation could change the electronic properties of melanin and might enhance the growth of melanize...

The effect of ionizing radiation on neuronal membrane function was assessed by measurement of neurotoxin-stimulated 22Na+ uptake by rat brain synaptosomes. High-energy electrons and gamma photons were equally effective in reducing the maximal uptake of 22Na+ with no significant change in the affinity of veratridine for its binding site in the channel. Ionizing radiation reduced the veratridine-...

mobile phone use and wireless communication technology have grown explosively over the past decades. this rapid growth has caused widespread global concern about the potential detrimental effects of this technology on human health. stem cells generate specialized cell types of the tissue in which they reside through normal differentiation pathways. considering the undeniable importance of stem ...

Background: Although ionizing radiation is widely used to diagnose many diseases, the relevant hazards are known to be as an important limitation of its application. It is believed that the awareness of ionizing radiation dose values is one of the main stages in patient's radiation protection. The purpose of this study has been to investigate the level of physicians' knowledge about radiation d...

As diversity in amphibian species declines, the search for causes has intensified. Work in this area has shown that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone ...

Introduction: Hesperidin (HES), as the most abundant flavonoid existing in the citrus, is widely used by human daily. The radio-protective effects of Hesperidin have been confirmed in various measurement systems. This study aimed to evaluate the effects of Hesperidin on the changes in the apoptosis level and expression of apoptotic genes target (bax, bcl-2 and ration of bax/bcl-2) in the periph...

Humic substances, i.e. dark paramagnetic polymeric anionic polyelectrolytes, belong to the most widespread macromolecular substances of biogenic origin in soil and aquatic environments. The exact structure of humic substances is unknown because of their complexity resulting from unrecurring precursors, from their composition and their process of synthesis. Degradation processes of these substan...

Loss of p53 function has been shown to cause increased resistance to ionizing radiation in normal murine cells; however, the role of p53 in radioresistance of human tumor cells is less clear. Since wild-type p53 function is required for radiation-induced G1 arrest, we measured G1 arrest in 12 human tumor cell lines that have a wide range of radiosensitivities (surviving fraction at 2 Gy, 0.11-0...

Different types of ionizing radiation produce different dependences of cancer risk on radiation dose/dose rate. Sparsely ionizing radiation (e.g. γ-rays) generally produces linear or upwardly curving dose responses at low doses, and the risk decreases when the dose rate is reduced (direct dose rate effect). Densely ionizing radiation (e.g. neutrons) often produces downwardly curving dose respon...