| || Models for the Development of Radiation Countermeasures (Review Paper)
Author : Kumar, Indracanti Prem;Gupta, Damodar;Bhatt, Anant Narayan;Dwarakanath, B.S.
Source : Defence Science Journal ; Vol:61(2) ; 2011 ; pp 146-156
Subject : 535.374 Radiation Hazards
Keywords : Radiation countermeasures;ionising radiation;radiation damage;radiation injury
Abstract : Appropriate models are essential for making the transition from scientific discoveries to meaningful applications of the knowledge for human use. Acute as well as delayed effects of ionising radiation to the biological systems develop hierarchically starting from damage to the vital macromolecules up to the disturbances caused at the whole organism level. In vitro models like bacteria, yeast, various mammalian cells cultured as monolayers (2-D) and spheroids (3-D) as well as cells with specific genetic alterations have provided insight into the complex relationships between damage induction and various signal transduction pathways, allowing identification of molecular and sub-cellular targets vital to the fate of irradiated cells. On the other hand, in vivo models (multicellular whole organisms), ranging from simple worms to non-human primates, have been gainfully employed to evaluate efficacy as well as toxicity of potential countermeasure agents (molecules, combinations and formulated preparations) facilitating their deployment in human subjects. This review provides a brief account of the efforts with various in vitro and in vivo models for understanding the biological basis of radiation damage as well as the development of radiation countermeasures, viz., protectors, mitigators and therapeutics.
| || Predictive Genomics: A Post-genomic Integrated Approach to Analyse Biological Signatures of Radiation Exposure
Author : Jayapal, Manikandan;Sethu, Swaminathan;Zeegers, Dimphy;Banerjee, Birendranath;Hande, M. Prakash
Source : Defence Science Journal ; Vol:61(2) ; 2011 ; pp 133-137
Subject : 535.374 Radiation Hazards
Keywords : ionising radiation;Biomarkers;genomics;microarray;genomic integration;biodosimetry;predictive genomics;genomic signatures;transcriptomic analysis
Abstract : The ultimate objective of radiation research is to link human diseases with the altered gene expression that underlie them and the exposure type and level that caused them. However, this has remained a daunting task for radiation biologists to indent genomic signatures of radiation exposures. Transcriptomic analysis of the cells can reveal the biochemical or biological mechanisms affected by radiation exposures. Predictive genomics has revolutionised how researchers can study the molecular basis of adverse effects of exposure to ionising radiation. It is expected that the new field will find efficient and high-throughput means to delineate mechanisms of action, risk assessment, identify and understand basic mechanisms that are critical to disease progression, and predict dose levels of radiation exposure. Previously, we have shown that cells responding to environmental toxicants through biological networks that are engaged in the regulation of molecular functions such as DNA repair and oxidative stress. To illustrate radiation genomics as an effective tool in biological dosimetry, an overview has been provided of some of the current radiation genomics landscapes as well as potential future systems to integrate the results of radiation response profiling across multiple biological levels in to a broad consensus picture. Predictive genomics represents a promising approach to high-throughput radiation biodosimetry.