الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Current radiation biodosimetry approaches include physical effects such as blood lymphocyte kinetics and time to emesis, as well as assessing chromosome aberrations in biodosimetry of cytogenetic which induced by radiation in circulating blood lymphocytes (Fenech, 2011). But these methods are too time-consuming. In addition to changes in transcripts, protein expression represents another method. that has the potential to provide excellent throughput for estimating exposure dose (Budworth et al., 2012).
This current study aimed to verify highly reproducible radiation-responsive genes (PCNA) Proliferating cell Nuclear Antigen and (POLH) Xeroderma pigmentosum variant genes as a Sensitive, Specific, and Dose-Dependent Biomarkers for Radiation Workers by using qRT-PCR.
The gene expressions (PCNA) Proliferating cell Nuclear Antigen and (POLH) Xeroderma pigmentosum in the whole blood was assayed using qRT-PCR technique in 73 subjects divided into 3 main groups (healthy control, radiation workers, cancer patients).
when assessing the acute radiation exposure (radiotherapy), The relative expression of the circulating POLH is downregulated in the patients after radiotherapy to about 20%, but for PCNA, it is downregulated in the patients after radiotherapy to about 7% of that in the before radiotherapy group. On the other hand, the circulating POLH and PCNA relative expression over the control subjects measured in occupational workers downregulation of POLH in the
Summary, C onclusions and Recommendations
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radiation workers to 0.3560 ± 0.1376 folds, but the level of the circulating PCNA is slightly upregulated in the radiation workers to 1.4365 ± 0.6465 folds relative to the control group which represent their differentiated behavior in different dose rates.
6.2 Conclusion
According to this present study, we can conclude the followings:
❖ Relative expression of the circulating POLH is downregulated in the radiation workers, and the level of the circulating PCNA is slightly upregulated in in the radiation workers relative to the control group.
❖ The relative expression of the circulating POLH and PCNA is downregulated in the patients after radiotherapy relative to the before radiotherapy group.
❖ POLH relative expression showed positive and significant correlation with the age in the radiation workers group.
❖ Different exposure rate affecting the gene expression behavior.
6.3 Recommendations
❖ Implementing the same experimental design on a larger target group.
❖ Investigate the target genes on different radiation workers category.
❖ Measures the proteins for the same genes expressions we used (POLH & PCNA).