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The knowledge of the radiation dose received by the patient during the radiological examination is essential to prevent risks of exposures. The aim of this work is to study patient doses for common diagnostic radiographic examinations in hospitals affiliated to Kashan University of Medical sciences, Iran. The results of this survey are compared with those published by some national and international values. Entrance surface dose (ESD) was measured based on the exposure parameters used for the actual examination and effective dose (ED) was calculated by use of conversion coefficients calculated by Monte Carlo methods. The mean entrance surface dose and effective dose for examinations of the chest (PA, Lat), abdomen (AP), pelvis (AP), lumbar spine (AP, Lat) and skull (AP, Lat) are 0.37, 0.99, 2.01, 1.76, 2.18, 5.36, 1.39 and 1.01 mGy, and 0.04, 0.1, 0.28, 0,28, 0.23, 0.13, 0.01 and 0.01 mSv, respectively. The ESDs and EDs reported in this study, except for examinations of the chest, are generally lower than comparable reference dose values published in the literature. On the basis of the results obtained in this study can conclude that use of newer equipment and use of the proper radiological parameter can significantly reduce the absorbed dose. It is recommended that radiological parameter in chest examinations be revised.

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Background: Radiation-induced heart injury can lead to increased risk of heart failure, attack, and ischemia. Some studies proposed IL-4 and IL-13 as two important cytokines that are involved in late effects of ionizing radiation. On the other hand, these cytokines may, through upregulation of Duox1 and Duox2, induce chronic oxidative stress, inflammation, and fibrosis. In this study, we evaluated the upregulation of Duox1 and Duox2 pathways in hearts following chest irradiation in rats and then detected possible attenuation of them by melatonin. Materials and Methods: Twenty male Wistar rats were divided into four groups: (1) control; (2) melatonin treated (100 mg/kg); (3) radiation (15 Gy gamma rays); (4) melatonin treated before irradiation. All rats were sacrificed after 10 weeks and their heart tissues collected for real-time PCR (RT-PCR), ELISA detection of IL-4 and IL-13, as well as histopathological evaluation of macrophages and lymphocytes infiltration. Results: Results showed an upregulation of IL-4, IL4ra1, Duox1, and Duox2. The biggest changes were for IL4ra1 and Duox1. Treatment with melatonin before irradiation could attenuate the upregulation of all genes. Melatonin also caused a reduction in IL-4 as well as reverse infiltration of inflammatory cells. Conclusion: Duox1 and Duox2 may be involved in the late effects of radiation-induced heart injury. Also, via attenuation of these genes, melatonin can offer protection against the toxic effects of radiation on the heart.

The present study examines blood metals levels and health parameters in dairy cows reared in areas around a Pb-Zn industrial complex located near the city of Zanjan-Iran. Blood samples (n = 27) were collected from cows reared around the smelter. Blood samples (n = 25) were also collected from cows reared in areas where chances of Pb contamination of soil, water and fodder do not exist, to serve as reference. The mean blood Pb level in cows around the smelter (1.09 ± 0.26 µg/mL) was higher than the cows from the reference area (0.72 ± 0.25 µg/mL). Hematocrit (PCV) levels decreased in cows reared in the near of smelter (24.37 % ± 2.22 %) compared to the reference site (27.54 % ± 2.87 %). Hemoglobin (Hb) concentration and mean corpuscular Hb concentration value in cows from the area around the smelter were statistically lower than the cows reared in reference area. Activities of alanine transaminase and aspartate aminotransferase (IU/l) were significantly higher in cows around the smelter as compared to reference animals.

Despite an increasing surge in application of nanoparticles in industries, there is a serious lack of information concerning their impact on human health and the environment. The present study investigated effects of molybdenum nanoparticles (Mo NPs) injected intraperitoneally into Sprague-Dawley rats at different doses of Mo NPs (5, 10, and 15 mg/kg BW per day) during a period of 28 days. Hematological and biochemical parameters as well as sexual hormones and histopathological examinations of the liver and testis were assessed and compared with control group. The results showed that the serum levels of testosterone decreased significantly in both groups of 10 and 15 mg (Mo NPs)/kg BW in comparison with the control group (p < 0.05). However, there were insignificant differences observed in luteinizing hormone (LH) levels and hematological parameters when compared with the control group (p > 0.05). The results of liver enzymes showed that serum levels of aspartate aminotransferase (AST) decreased significantly in both dosage groups of 5 and 10 mg/kg BW (Mo NPs) when compared with the control group (p < 0.05), and significant decrease obtained in lactate dehydrogenase (LDH) levels at dose of 5 mg/kg BW in comparison with the control group (p < 0.05). The histopathological examination of testis showed a decrease in number of Leydig cells. Also, the number of chronic inflammatory cells increased in portal triad and parenchyma in liver tissue of rats exposed to Mo NPs.

This study aimed to determine the effects of melatonin on irradiation‐induced apoptosis and oxidative stress in the brainstem region of Wistar rats. Therefore, the animals underwent whole‐brain X‐radiation with a single dose of 25 Gy in the presence or absence of melatonin pretreatment at a concentration of 100 mg/kg BW. The rats were allocated into four groups (10 rats in each group): namely, vehicle control (VC), 100 mg/kg of melatonin alone (MLT), irradiation‐only (RAD), and irradiation plus 100 mg/kg of melatonin (RAM). An hour before irradiation, the animals received intraperitoneal (IP) melatonin and then were killed after 6 hr, followed by measurement of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant capacity (TAC) in the brainstem region. Furthermore, the western blot analysis technique was performed to assess the caspase‐3 expression level. Results showed significantly higher MDA and NO levels in the brainstem tissues for the RAD group when compared with the VC group (p < .001). Moreover, the irradiated rats exhibited a significant decrease in the levels of CAT, SOD, GPx, and TAC (p < .01, p < .001, p < .001, and p < .001, respectively) in comparison to the VC group. The results of apoptosis assessment revealed that the expression level of caspase‐3 significantly rose in the RAD group in comparison with the VC group (p < .001). Pretreatment with melatonin ameliorated the radiation‐induced adverse effects by decreasing the MDA and NO levels (p < .001) and increasing the antioxidant enzyme activities (p < .001). Consequently, the caspase‐3 protein expression level in the RAM group showed a significant reduction in comparison with the RAD group (p < .001). In conclusion, melatonin approximately showed a capacity for neuroprotective activity in managing irradiation‐induced oxidative stress and apoptosis in the brainstem of rats; however, the use of melatonin as a neuroprotective agent in humans requires further study, particularly clinical trials.