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1.
Environ Sci Pollut Res Int ; 27(8): 8684-8695, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31904099

ABSTRACT

Exposure to ionizing radiation emitted from natural sources induces many health hazards. The response to ionizing radiation involves a number of mediators including inflammatory cytokines and free radicals which mediate immunosuppression. The present study aimed to monitor the impact of exposure to natural radioactive rocks from the Egyptian eastern desert on the primary immune organs. Therefore, three experimental groups (15 rats per group) were used: group I included the control non-irradiated rats; group II included rats that were exposed for 28 consecutive days to natural radioactive rocks from the Egyptian eastern desert (IR/R group); and group III (positive control group) included rats that were exposed to high dose of γ-rays (4 Gy/14 days for 28 days) (IR/γR group). We found that rats of both the IR/R and IR/γR groups exhibited pathological alterations in the architecture of the primary immune organs (bone marrow and thymus). Additionally, the levels of C-reactive protein (CRP), proinflammatory cytokines (IL-1ß, IL-6 and TNF-α), and reactive oxygen species (ROS) were significantly increased in the IR/R and IR/γR groups compared to the control group. Furthermore, rats from the IR/R and IR/γR groups exhibited significant increase in the activity of caspase-3 and caspase-9 and subsequently exhibited a significant increase in the apoptosis of PBMCs compared with the control group. Most importantly, apoptosis induction in the PBMCs was associated with increased expression of cyclin B1 and decreased expression of cyclin D1 and survivin compared with the control non-irradiated group. Taken together, our data demonstrated that consecutive exposure to natural radioactive rocks from the Egyptian eastern desert could dampen the immune response through damaging the architectures of the immune system and mediating serious health problems to the population inhabiting this region.


Subject(s)
Apoptosis , Background Radiation , Radiation Exposure/analysis , Radiation, Ionizing , Animals , Egypt , Lymphocytes , Male , Rats , Reactive Oxygen Species
2.
Environ Sci Pollut Res Int ; 25(29): 29541-29555, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30136187

ABSTRACT

The distribution of the natural radioisotopes 238U, 226Ra, 232Th, and 40K in addition to their radiological parameters in granitic rock samples from five different localities (Gebel El-Missikat, Gebel El-Gidamy, Gebel Ria El-Garra, Gebel El-Aradiya, and Gebel Kab Amira) in the central area of the Eastern Desert, Egypt, was measured using high purity germanium (HPGe) detector-based γ-spectrometry. The average activity concentrations of 238U, 226Ra, 232Th, and 40K in all five studied areas are higher than the corresponding global average values. The highest average activity concentrations of 238U and 226Ra were observed in Gebel El-Missikat, whereas the highest average value of 232Th activity concentration was found at Gebel El-Gidamy, and the highest concentration of 40K was obtained at Gebel El-Aradiya. The radiological hazard parameters radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin), absorbed dose rate (ADR), annual effective dose rate (AEDR) outdoors, annual gonadal dose equivalent (AGDE), and excess lifetime cancer risks (ELCR) were calculated to assess the radiation hazards associated with the rock samples. The average values of these parameters are higher than the recommended reference levels. The obtained data provide a valuable future database for estimating the impact of radioactive contamination in the studied area and in the places where the rocks are used.


Subject(s)
Geologic Sediments/chemistry , Radiation Monitoring/methods , Radioactivity , Silicon Dioxide/chemistry , Soil Pollutants, Radioactive/analysis , Desert Climate , Egypt , Humans , Radioisotopes/analysis , Spectrometry, Gamma
3.
Environ Sci Pollut Res Int ; 20(12): 8700-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23716081

ABSTRACT

The natural radioactivity of soil samples from Assiut city, Egypt, was studied. The activity concentrations of 28 samples were measured with a NaI(Tl) detector. The radioactivity concentrations of (226)Ra, (232)Th, and (40)K showed large variations, so the results were classified into two groups (A and B) to facilitate the interpretation of the results. Group A represents samples collected from different locations in Assiut and characterized by low activity concentrations with average values of 46.15 ± 9.69, 30.57 ± 4.90, and 553.14 ± 23.19 for (226)Ra, (232)Th, and (40)K, respectively. Group B represents samples mainly collected from the area around Assiut Thermal Power Plant and characterized by very high activity concentrations with average values of 3,803 ± 145, 1,782 ± 98, and 1,377 ± 78 for (226)Ra, (232)Th, and (40)K, respectively. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose rate (E), the external hazard index (H ex), and the annual gonadal dose equivalent (AGDE) have been calculated and compared with the internationally approved values. For group A, the calculated averages of these parameters are in good agreement with the international recommended values except for the absorbed dose rate and the AGDE values which are slightly higher than the international recommended values. However, for group B, all obtained averages of these parameters are much higher by several orders of magnitude than the international recommended values. The present work provides a background of radioactivity concentrations in the soil of Assiut.


Subject(s)
Radiation Monitoring , Soil Pollutants, Radioactive/analysis , Egypt , Potassium Radioisotopes/analysis , Power Plants , Radioactivity , Radium/analysis , Soil/chemistry , Thorium/analysis
4.
Environ Sci Pollut Res Int ; 20(9): 6331-6, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23589256

ABSTRACT

Heavy fuel oil and ash samples were collected from the Assiut thermal power plant in Egypt and subjected to gamma spectrometry analysis for natural radioactivity contents. Considerable results were observed where the ash contains nearly 1,000 times natural radionuclides more than raw oil. The results were confirmed by measuring the samples via using different devices in different institutions. All ash samples had radium equivalent activities and external hazard index values more than 370 Bq/kg and unity respectively. The mean absorbed dose rate was10,650 nGy/h which is nearly 190 times higher than the global average value of 55 nGy/h. The corresponding annual external effective dose is estimated to be 13 mSv/year, which is nearly 30 times higher than that in areas of natural background radiation (0.46 mSv/year).


Subject(s)
Coal Ash , Environmental Monitoring , Environmental Pollutants/adverse effects , Environmental Pollutants/chemistry , Fuel Oils/adverse effects , Egypt , Fuel Oils/analysis
5.
Acta Otolaryngol ; 123(2): 325-9, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12701768

ABSTRACT

OBJECTIVE: To evaluate endoscopic and external dacryocystorhinostomy (DCR) using a quantitative, objective functional tool. MATERIAL AND METHODS: This study comprised 58 cases divided into 4 groups: healthy controls; patients suffering from epiphora due to nasolacrimal duct (NLD) obstruction; patients who had undergone endoscopic DCR; and patients who had undergone external DCR. The lacrimal sac pressure was measured during blinking, forced blinking and the Valsalva maneuver using a polygraph. RESULTS: Negative pressure was detected during blinking and forced blinking in all normal subjects and in most patients who had successfully undergone DCR. In contrast, positive pressure was detected in cases with epiphora and patients in whom DCR had failed. Negative pressure was higher after endoscopic than external DCR. During the Valsalva maneuver there were no pressure changes in normal cases and patients with epiphora. In contrast, positive pressure was detected after all of the successful procedures (being higher after external than endoscopic DCR) and in most of the patients in whom external DCR failed. CONCLUSIONS: In normal subjects, negative pressure is created during blinking. In cases with epiphora due to NLD obstruction, the lacrimal pump is affected but its function is restored after successful DCR. The suction power of the pump mechanism is more effective after endoscopic than external DCR.


Subject(s)
Dacryocystorhinostomy/methods , Endoscopy/methods , Lacrimal Apparatus/physiology , Adolescent , Adult , Aged , Case-Control Studies , Child , Female , Follow-Up Studies , Humans , Lacrimal Apparatus Diseases/diagnosis , Lacrimal Apparatus Diseases/surgery , Lacrimal Duct Obstruction/diagnosis , Male , Manometry/methods , Middle Aged , Postoperative Period , Pressure , Prospective Studies , Reference Values , Treatment Outcome
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