Assessment of radiation exposure risks in patients undergoing elastic stable intramedullary nailing: Insights from intraoperative fluoroscopy.

INTRODUCTION: Elastic stable intramedullary nailing (ESIN) is a well-defined and appropriate treatment of choice for long bone fractures. Despite its benefits, the risk of cancer from imaging devices is of particular concern for younger adults. So, this survey was conducted to estimate the doses administered to patients undergoing ESIN of long bone fractures utilizing a 2-dimensional (2D) C-arm fluoroscopy machine during surgery, as well as the carcinogenic risk associated with the use of the machine. METHODS: This study was conducted on 147 patients who required ESIN for long-bone fractures. Patients' demographic data, surgical data and imaging information were collected. For each patient, the organ doses and the effective doses were computed with the Monte Carlo PCXMC 2.0 simulation software. The cancer risk models proposed in the Biological Effects of Ionizing Radiation VII (BEIR VII) Phase 2 report were used to evaluate the risk of exposure-induced cancer death (REID) values. RESULTS: For all patients, the highest organ dose was delivered to the gonads. The mean effective dose was 0.026 ± 0.015 mSv and 1.3E-04 ± 1E-04 mSv for ESIN of femur and tibia fractures, respectively. Males had a mean REID of 1 per million, while females had a mean REID of 0.19 per million. The younger males had considerably higher REID values. The effective dose was significantly correlated with age, gender, and irradiation time. CONCLUSION: Low levels of effective doses and cancer risks associated with the utilization of the fluoroscopy machine in current practice were found in ESIN treatment of long-bone fractures. IMPLICATIONS FOR PRACTICE: This outcome will help to raise surgeons' awareness of radiation risks and encourage them to initiate measures to keep radiation dose and exposure time as low as reasonably achievable.

Evaluating Gamma-H2AX Expression as a Biomarker of DNA Damage after X-ray in Angiography Patients.

OBJECTIVE: Coronary heart disease (CHD) is one of the most common diseases. Coronary angiography (CAG) is an important apparatus used to diagnose and treat this disease. Since angiography is performed through exposure to ionizing radiation, it can cause harmful effects induced by double-stranded breaks in DNA which is potentially life-threatening damage. The aim of the present study is to investigate phosphorylation of Histone H2AX in the location of double-stranded breaks in peripheral blood lymphocytes as an indication of biological effects of radiation on angiography. MATERIALS AND METHODS: This method is based on the phosphorylation measurement of Histone (gamma-H2AX or γ-H2AX) levels on serine 139 after the formation of DNA double-strand break. 5 cc of blood samples from 24 patients undergoing angiography were taken pre- and post-radiation. Blood lymphocytes were extracted, fixed and stained with specific γ-H2AX antibodies. Finally, the percentage of phosphorylation of Histone H2AX as an indicator of double-strand break was measured by a cytometry technique. RESULTS: An increase was observed in all patients' percentage of phosphorylated Histone H2AX (double-stranded breaks DNA) after radiation (20.15 ± 14.18) compared to pre-exposure time (1.52 ± 0.34). Also, the mean of DNA double-strand break is shown in a linear correlation with DAP. DISCUSSION: Although induction of DNA double-strand breaks was associated with the radiation dose in patients, the effect of individual factors such as radio-sensitivity and regenerative capacity should not be ignored. In the future, if we are able to measure DNA damage response in every angiography patient, we will use it as a biomarker for the patient dose; this will promote public health. CONCLUSION: Using flow cytometers readings done automatically is possible to detect γ-H2AX in the number of blood cells, therefore, the use of this technique could play a significant role in monitoring patients.

Evaluating Radioprotective Effect of Hesperidin on Acute Radiation Damage in the Lung Tissue of Rats.

BACKGROUND: Oxidative stress plays an important role in the pathogenesis and progression of γ-irradiation-induced cellular damage, Lung is a radiosensitive organ and its damage is a dose-limiting factor in radiotherapy. The administration of dietary antioxidants has been suggested to protect against the succeeding tissue damage. The present study aimed to evaluate the radioprotective efficacy of Hesperidin (HES) against γ-irradiation-induced tissue damage in the lung of male rats. MATERIALS AND METHODS: Thirty two rats were divided into four groups. Rats in Group 1 received PBS and underwent sham irradiation. Rats in Group 2 received HES and underwent sham irradiation. Rats in Group 3 received PBS and underwent γ-irradiation. Rats in Group 4 received HES and underwent γ-irradiation. These rats were exposed to γ-radiation 18 Gy using a single fraction cobalt-60 unit, and were administered HES (100 mg/kg/d, b.w, orally) for 7 days prior to irradiation. Rats in each group were sacrificed 24 hours after radiotherapy (RT) for the determination of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and histopathological evaluations. RESULTS: Compared to group 1, the level of SOD and GSH significantly decreased and MDA level significantly increased in group 3 at 24 h following irradiation, (p=0.001, p<0.001, p=0.001), respectively. A statistically significant difference in all parameters was observed for rats in group 4 as compared to group 3 (p<0.05). Histopathological results 24 hours after RT showed that radiation has increased inflammation, lymphocyte, macrophage and neutrophil compared to group 1 ( p<0.0125). Oral administration of HES before RT significantly decreased macrophage and neutrophil when compared to group 3 (p<0.0125), but partly there was inflammation and lymphocyte that indicated there was no significant difference when compared to group 3 (p>0.0125). CONCLUSION: Oral administration of HES was found to offer protection against γ-irradiation- induced pulmonary damage and oxidative stress in rats, probably by exerting a protective effect against inflammatory disorders via its free radical scavenging and membrane stabilizing ability.

Effects of Hesperidin as a Radio-protector on Apoptosis in Rat Peripheral Blood Lymphocytes after Gamma Radiation.

INTRODUCTION: Hesperidin (HES), as the most abundant flavonoid existing in the citrus, is widely used by human daily. The radio-protective effects of Hesperidin have been confirmed in various measurement systems. This study aimed to evaluate the effects of Hesperidin on the changes in the apoptosis level and expression of apoptotic genes target (bax, bcl-2 and ration of bax/bcl-2) in the peripheral blood lymphocytes of male rats after gamma radiation. MATERIALS AND METHODS: 64 male rats were divided into eight groups: Control, HES (100 mg/kg b.w, orally, 7 days), whole body irradiation with 2 and 8Gy, pre-administrated with 50 and 100 mg/kg body weight of Hesperidin for 7 days before irradiation with 2 and 8 Gy. 24 hours after radiation, apoptotic lymphocytes were evaluated using PE Annexin V Apoptosis detection I kit and the levels of mRNA for bax and bcl-2 were evaluated by real time reverse transcription polymerase chain reaction. RESULTS: A significant reduction in apoptosis of the lymphocytes was demonstrated in group animals receiving 8 Gy compared to the group which received 2 Gy irradiation (p<0.0001). However, apoptosis significantly increased in group of rats who received Hesp before irradiation (p<0.05). The increase of apoptosis by Hesperidin administration can be attributed to the decreased expression of bax and significantly reduced expression of bcl-2 and finally increasing the ration of bax/bcl-2. CONCLUSION: The results suggest that administration of 50 and 100 mg/kg of Hesperidin induces apoptotic effects by changing expression level of bax, bcl-2 and also the ratio of bax/bcl2.

The mechanisms of radiation-induced bystander effect.

The radiation-induced bystander effect is the phenomenon which non-irradiated cells exhibit effects along with their different levels as a result of signals received from nearby irradiated cells. Responses of non-irradiated cells may include changes in process of translation, gene expression, cell proliferation, apoptosis and cells death. These changes are confirmed by results of some In-Vivo studies. Most well-known important factors affecting radiation-induced bystander effect include free radicals, immune system factors, expression changes of some genes involved in inflammation pathway and epigenetic factors.