background: increasing the complexity in modern radiotherapy techniques have increased the delivery time lowering consequently the treatment efficacy. through simulating the delivery time delay encountered in such techniques, its’ effect on two cancer cell lines and the compensating doses given to prevent such effect was investigated. materials and methods: f10b16 and 4t1 cancer cell lines were...

We previously reported that methoxyamine (an inhibitor of base excision repair) potentiates iododeoxyuridine (IUdR)-induced radiosensitization in human tumor cells. In this study, we investigated the potential mechanisms of this enhanced cell death. Human colorectal carcinoma RKO cells were exposed to IUdR (3 micromol/L) and/or methoxyamine (3 mmol/L) for 48 hours before ionizing radiation (5 G...

The primary purpose of this chapter is to provide public health officials, toxicologists, and other interested individuals and groups with an overall perspective of the health physics and toxicology of ionizing radiation. It contains descriptions and evaluations of radiological and toxicological studies and epidemiologic investigations and provides conclusions, where possible, on the relevance ...

Exposure to ionizing radiation has potential for acute and chronic health effects. Within the general public of the United States, there may be a discrepancy between perceived and actual health risks. In conjunction with the Vermont Department of Health, a survey designed to assess public perception and knowledge of ionizing radiation was administered at 6 Vermont locations (n = 169). Descripti...

Radiation therapy is an effective cancer therapy, but damage to normal tissues surrounding the tumor due to radiotherapy causes severe complications. The importance of the therapeutic area between tumor suppression and normal tissue injury has long been highlighted in radiation therapy. Recent advances in stem cell biology have shown that stem cell (SC) responses to genotoxic stresses of ionizi...

Evidence of health benefits and longer average life-span following low-dose irradiation should replace fear, “all radiation is harmful,” and “the perception of harm” as the basis for action in the 21 century. Hormesis is the excitation, or stimulation, by small doses of any agent in any system. Large doses inhibit. “Low dose” is defined as any dose between ambient levels of radiation and the th...

Background: Nowadays, radiotherapy is used effectively for treatment of head and neck cancers. Mucositis is one of the most important side effects of radiotherapy. Radio-protective agents protect tissues and cells against the adverse effects due to ionizing radiation and cleave radiation-induced free radicals. Lycopene as a potent antioxidant protects cells against oxidative damage by free radi...

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing ...