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Document Type |
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Thesis |
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Document Title |
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Effect of ionizing radiation dose on the blood cells in rats تأثير جرعة الإشعاع المؤين على خلايا الدم في الفئران |
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Subject |
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physics department |
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Document Language |
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Arabic |
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Abstract |
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Biota are exposed to ionizing radiation in many situations such as cosmic rays, nuclear disasters like Chernobyl or Fukushima, occupational works, and medical centers. Currently, neutron beam is used in many medical applications where neutrons produce free radicals that change the submolecular level of proteins, membrane lipids, and DNA. This study aims to investigate the effect of very low neutrons dose on blood cells. 16 Female Wistar rats were irradiated with neutrons of 0.009 Gy (241Am-Be) and 16 were used as control. Blood samples were taken at the 0, 4th, 8th, and 12th day postirradiation. Fourier transform infrared (FTIR) spectroscopy was used to record the lyophilized erythrocytes and mononuclear cells spectra. Second derivative and curve fitting were applied on the FTIR spectra. Hierarchical cluster analysis (HCA) was used to classify group spectra. Comet assay (CA) has been used to evaluate the damage of DNA in the leukocytes. Changes in erythrocytes appeared only in 4 days postirra-diation group. Second derivatives of FTIR spectral showed significant changes in the methylene area. Curve fitting showed an increase in the percentage area of alpha helix opposing a decrease in the beta-structure in the secondary protein structure that was elucidated by protein denaturation. Ratio measurements revealed a noticeable increase in the erythrocytes polarity referred to an increase in the Van der Waals forces. Packing and hydrocarbon chain length showed a marked decrease that was attributed to reactive oxygen species attacks during oxidative stress. For mononuclear cells, HCA distinguished the irradiated rats from the control in the 0 and 4 days postirradiation groups. Percentage area of alpha helix showed a significant decrease opposing an increase in the beta-structure in the 4 days postirradiation group. At 0 day, phospholipids of nucleic acids and RNA ribose showed a significant increase and decrease in the area bands, respectively, which were considered as an evidence of a double strand break, and incorrect translation processes, respectively. A significant decrease in the RNA/DNA was attributed to the fragmentation of the chromatin. At the 4 days postirradiation, Methylene bands of erythrocytes and mononuclear shifted towards lower frequencies associated to low membrane fluidity. CA revealed low-level damage in DNA. From this study, it may be concluded that the very low dose of radiation could cause oxidation stress. The effects of irradiation on cell membrane and protein appear after few days postirradiation whereas, the effects on the DNA appear directly postirradiation. |
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Supervisor |
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Dr. Sherif Nafee |
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Thesis Type |
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Master Thesis |
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Publishing Year |
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1435 AH
2013 AD |
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Co-Supervisor |
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Dr. Salem Shaheen . Dr. Gehan Abdel Raouf |
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Added Date |
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Monday, February 10, 2014 |
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Researchers
| عـبده سعـيد عـبدالله | Abdullah, Abdu Saeed | Researcher | Master | |
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