[en] The need for reliable and routine tests to determine whether or not food has been irradiated has arisen as a result of the progress made in commercialization of the food irradiation technology. The effectiveness of food irradiation depends on proper delivery of absorbed dose and its reliable measurement. Electron Paramagnetic Resonance (EPR) spectroscopy has been established as an essential tool both for detection of irradiated food and radiation measurements. This presentation demonstrates the behavior of the radicals produced in irradiated cashew nut and orange. In addition the role of EPR spectroscopy will be discussed to understand thermoluminescence behavior of CaSO_4 dosimeter. Cashew nut and orange samples were exposed to gamma radiation in the dose range of 0.25 to 2 kGy. CaSO_4 crystals were irradiated at 0.5-7 kGy. Electron Paramagnetic Resonance (EPR) spectroscopy was carried out using EMX model EPR spectrometer (BRUKER, Germany) with a microwave frequency of 9.42 GHz

[en] Human population is encountering increasing levels of illness caused by conditions such as stroke, ischaemic heart disease, diabetes, and cancer. Use of radiation has revolutionized the medical fields, enhancing the ability of medical professionals to treat and diagnose diseases. However, the benefit of radiation technology in health care is significantly under-resourced. Department of Atomic Energy (DAE) envisions eradicating the health havoc by providing affordable and accessible diagnostic, therapeutic and palliative care services. To this end, DAE is vigorously pursuing its plan to bring radiation and nuclear technologies to the poorest of poor at every corner of our country for health care. Molecular level research is encouraged on biochemical pharmacology, computational biology and rational drug design, and exploration of the great Indian biodiversity to develop new drugs/formulations that can improve the efficacy of the existing drugs as well as radiation therapy. This conference helps in bringing to light the issues regarding modalites for human diseases to improve life qualities of all sections of people. Papers relevant to INIS are indexed separately

[en] Nuclear and radiological accidents which result in radiation emergencies causing different types of radiation injuries are infrequent in occurrence and unique in character. As a matter of fact deaths that have resulted so far due to major radiation/nuclear accidents in nuclear industry, non-nuclear industry using ionizing radiation, research and medicine involving workers as well as members of the public have been around 120 throughout the world except of course excluding the death toll due to atomic bomb explosions. Nevertheless ever increasing and proliferative use of radioactive materials in industry, agriculture, power generation, medicine, research and for military purposes (nuclear weapons) including nuclear terrorism has increased several folds the potentiality of occurrence of radiation emergencies

[en] Uranium present in phosphate fertilizer contaminates agricultural land. Uranium exerts chemical toxicity to the resident biota as it induces oxidative stress by generating free radicals. Two strains of nitrogen fixing cyanobacteria viz., Anabaena PCC 7120 and L-31 native to Indian paddy, regularly experience oxidative stress induced by different stresses and heavy metals. The present study investigated their response to uranium exposure at proteomic level. LD_5_0 dose for Anabaena 7120 and Anabaena L-31 was determined to be 75 μM and 200 μM uranyl carbonate exposure for 3 h. A total of 79 proteins from Anabaena 7120 and 64 proteins from Anabaena L-31 were identified by MALDI mass spectrometry, of which levels of 45 and 27 proteins respectively were found to be differentially modulated in the two strains in response to uranium exposure. The differentially expressed proteins belonged to the major functional categories of photosynthesis, carbon metabolism and oxidative stress alleviation, commensurate with their uranium tolerance. Better oxidative stress management, and maintenance of metabolic and energy homeostasis lead to superior uranium tolerance in Anabaena L-31 as compared to Anabaena PCC 7120

[en] The membrane integrity of circulating red blood cells (RBCs) is compromised by the deleterious actions of γ-radiation in humans. Grapes are the richest source of antioxidants due to presence of potentially bioactive phytochemicals. The objective of the present study was to assess the radioprotective actions of grape extracts against the γ-radiation-induced membrane permeability of human erythrocytes. The scavenging activities in seeds of grape in DPPH, hydrogen peroxide and hydroxyl radicals, were higher than skin or pulp of different cultivars. Grape extracts also showed appreciable extent of total antioxidant capacity and effective antihemolytic action. Grape extracts significantly ameliorated the γ-radiation-induced increase of the levels of thiobarbituric acid-reactive substances (TBARS, an index of lipid peroxidation) in the RBC membrane ghosts. Stored blood showed higher levels of K"+ ion as compared to the normal blood which was elevated by γ-radiation. Membrane ATPase was inhibited by the exposure to γ-radiation.Treatment of RBCs with the grape extracts prior to the exposure of γ-radiation significantly mitigated these changes in the erythrocyte membranes caused by the lower dose of radiation (4 Gy). (author)

[en] In response to radiation-induced DNA damage, eukaryotic cells initiate a complex signalling pathway, termed the DNA damage response (DDR), which coordinates cell cycle arrest with DNA repair. Previous study showed that induction of G1 arrest in response to radiation induced DNA damage is minimally a two-step process: a fast p53-independent initiation of G1 arrest mediated by cyclin D1 proteolysis and a slower maintenance of arrest resulting from increased p53 stability. We elucidated the molecular mechanism of slow and fast response of radiation induced DDR. We showed that FBXO31, a member of F-box family proteins, plays important role in DDR induced by ionizing radiation. We show that FBXO31 is responsible for promoting MDM2 degradation following radiation. FBXO31 interacts with and directs the degradation of MDM2 in ATM dependent phosphorylation of MDM2. FBXO31-mediated loss of MDM2 leads to elevated levels of p53, resulting in growth arrest. In cells depleted of FBXO31, MDM2 is not degraded and p53 levels do not increase following genotoxic stress. Thus, FBXO31 is essential for the classic robust increase in p53 levels following DNA damage

[en] Ionizing radiation acts by damaging DNA, causing various chromosomal anomalies, among which dicentric is the main aberration which is analyzed by biological dosimetry. The dose value obtained by referring a measured yield of aberrations to a calibration curve represents an average absorbed dose to the lymphocytes. Data analyzed with one way ANOVA showed significant difference between mean number of dicentric chromosome on designated days with p value <0.000. As compared to day 0 mean dicentric chromosomes on day 1,5,15 were significantly higher with p value <0.000 for day 1, 5, 15, 25 and non-significant at end of treatment and 6 weeks post treatment with p value 0.053 and 1.000, respectively. After analyzing metaphases, we observed that the yield of dicentrics increased with each successive fraction of radiation. However, the mitotic index decreased significantly with increasing doses of radiation

[en] Jivanti is a well-known Rasayana in Ayurveda and is being used as an ingredient in various formulations like Jivantadya Gharita, Jivatayadi rasa, Jivantayaditaila, Ashwagandhadi Gharita, Anuthaila, Chandanadithaila which are used in various diseases. Jivanti has been claimed to be useful as galactagogue, antibacterial, lactogenic, hypotensive, restorative, tonic and hypoglycaemic activity. In this study we have isolated aqueous crude extract of Jivanti powder and was evaluated for the presence of different phytochemicals using various qualitative and quantitative assays. Further its antioxidant capacity and radioprotective property were evaluated using various in vitro assays. The total antioxidant capacity was estimated by the DPPH, ABTS+ and NO radical scavenging assays. Its reducing power was analyzed by ferric reduction and Molybdenum reduction assays. At the end, radioprotective property was evaluated using plasmid relaxation, lipid peroxidation and propidium iodide staining. Our study shows that the yield of crude aqueous extract from the raw powder was 1.6%. It exhibited concentration dependent DPPH, ABTS+ and NO radical scavenging activity indicating its significant antioxidant capacity. This extract significantly inhibited DNA strand breaks in plasmid pBR322 DNA and peroxidation of membrane lipids against ionizing radiation. Jivanti crude extract decreased radiation induced cell death in splenocytesas monitored by propidium iodide staining. (author)

[en] Microtubules (MT) are dynamic structural cellular components. In proliferating cells, they are essential components in cell division through the formation of the mitotic spindle. Radiotherapy is an integral part of cancer treatment for most of the solid cancers. Scanty data exists in the literature related to how ionizing radiation affects microtubule reorganization in tumor cells. In the present study, breast cancer cell line (MCF-7 cells) was exposed to different doses of radiation (2-10Gy). Cells were cultured for 24 h, fixed and stained with antitubulin antibody and subjected to immunofluorescence microscopy. In another experiment, cells were subjected to cold treatment for 5 min or 30 min for studying the disassembly of microtubules after 24 h of irradiation. Further, these cells were incubated at 37°C for 20 min for studying the reassembly of microtubules. Acetylation of microtubule was also examined after exposure of cells to radiation. Experiments were also performed by combining radiation with low concentration of CXI-Benzo 84 (MT destabilizing agent 1 and 2.5 uM). Exposure of MCF-7 cells to radiation lead to destabilization of microtubules. Interestingly, destabilization of microtubule was faster upon cold treatment in irradiated group as compared to control group. These cells failed to re-stabilize at 37°C. Radiation also reduced the acetylation level of microtubule. Combination treatment of CXI-Benzo 84 with radiation exhibited additive effect in terms of depolymerization of MT. Our results suggest that ionizing radiation indeed modulates microtubule dynamics. (author)

[en] In view of the fact that radiotherapy fails in the later stages of cancer due to the radioresistant tumor cells, it is most important in radiobiology to enhance the oxidative damage of the tumor cells by using a tumor selective cytotoxic agent. The increase in radiosensitivity is important both for optimizing radiation dose for tumors and for designing strategies to improve the therapeutic ratio. Amount and time of treatment of radiation (IR), epigallocatechin gallate (EGCG) and epicatechin (EC) were determined using MTT assay. Biochemical assay, Flow cytometry and immune blots were employed to elucidate the enhanced sensitization of EC and EGCG along with IR in hepatocellular carcinoma cells (HepG2). The effects were more effective in killing the HepG2 cells compared to only irradiation. It was observed that the ROS generation was significantly increased in combination group (IR+EGCG/EC) over the IR group. Lower reduced glutathione content, higher TBARS and decreased catalase activity in combination group provided additive support. Combination treatment caused cell cycle arrest at G2/M phase. Mitochondrial membrane potential was greatly reduced and the percentage of apoptotic population increased in combination group compared to IR alone. Moreover, the higher expression of p53 and activation of caspase 3 in combination group over the IR alone indicated EC and EGCG along with ionizing radiation increase the oxidative stressed condition in HepG2 cell that leads the apoptosis of the cells. The novel use of this combination of radiation and tea polyphenol will remain an effective radiotherapeutic strategy. (author)