Browsing by Publisher "Novin Medical Radiation Institute"

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Bone marrow radiation dosimetry of high dose 131I treatment in differentiated thyroid carcinoma patients
    (Novin Medical Radiation Institute, 2016) Parlak Y.; Demir M.; Cavdar I.; Ereees S.; Gumuser G.; Uysal B.; Kaya G.C.; Koç M.; Sayit E.
    Background: Radiation absorbed dose to the red bone marrow, a critical organ in the therapy of thyroid carcinoma, is generally kept below 2 Gy for non-myeloablative therapies. The aim of this study was to calculate bone marrow radiation dose by using MIRDOSE3 package program and to optimize the safe limit of acivity to be administered to the thyroid cancer paients. Materials and Methods: In this study, 83 thyroid cancer patients were divided into 3 groups based on the amount of acivity administered into the body. In the groups, 3700 MBq, 5550 MBq and 7400 MBq activities were used respecively. The curves of ime-acivity were drawn from blood samples counts and effective half-life and residence time were calculated. Correlations of bone marrow radiation dose and radioiodine effective half-life were determined as a function of administered activity via ANOVA test. Tg levels and tumour diameters were compared using Spearman's correlation. Results: The effective half-lives of 131I for three groups of whole-body, receiving 3700 MBq, 5550 MBq and 7400 MBq were calculated as 20.57±5.4, 17.8±5.8 and 18.7±3.9 hours, respectively. The average bone marrow doses for 3 groups of patients were 0.32±0.08 Gy, 0.42±0.14 Gy and 0.60±0.24 Gy, respectively. Conclusion: It was concluded that, the bone marrow dose to the patients still remains within the recommended level even after administering an activity of 7400 MBq of 131I to the patients.
  • No Thumbnail Available
    Item
    PTX3 levels in murine pulmonary parenchymal tissues are correlated with radiation-induced injurie
    (Novin Medical Radiation Institute, 2020) Sarper B.; Ozbilgin M.K.; Gumustepe E.; Gencur S.; Karaman G.Z.; Kilicaslan P.; Kurtman C.
    Background: Pentraxins (PTX) play key roles in innate immunity and inflammatory responses. An increase in PTX3 levels may be a marker of early radiation injury in the lung. Thus, we aimed to determine the effect of radiation on PTX3 expression in a lung injury mouse model. Materials and Methods: Twenty-four 6–8-week-old mice were divided into 4 groups, one control (group 1) and three experimental groups (groups 2–4) irradiated with 6 MV photons and 5 Gy in a single fraction. Groups 2, 3, and 4 were sedated and euthanized 24, 72, and 168 h after radiation, respectively. The right lung middle lobe was then removed for histochemical examination and immunostaining for PTX3 expression, which was evaluated semi-quantitatively using H-SCORE analysis. Kolmogorov-Smirnov and Kruskal Wallis one-way analysis of variance were used for statistical analysis. Results: Immunohistochemistry of lung tissue samples showed different PTX3 expression levels across the four groups. Group 1 showed weak staining (232.50 ± 9.501), while group 2 (301.50 ± 7.472) and group 3 (283.50 ± 7.090) showed strong immunoreactivity. Group 4 showed moderate PTX3 immunoreactivity (271.50 ± 10.013). Moreover, H-score values between control and early radiation groups were statistically significant (group 1 vs. group 2, p < 0.001; group 1 vs. group 3, p = 0.002). Conclusion: PTX3 levels may be an early marker for long-term radiation effects. Our study provides insights into the pathological processes of pulmonary inflammation and acute radiation injury, and may provide novel therapeutic strategies for controlling pulmonary inflammation without eliciting radiation injury. © 2020 Novin Medical Radiation Institute. All rights reserved.
  • No Thumbnail Available
    Item
    Effects of adrenomeduline and ramp2 on the lung of mice exposed to total body radiation
    (Novin Medical Radiation Institute, 2020) Ozbilgin M.K.; Karaman G.Z.; Gencur S.; Gumustepe E.; Kurtman C.
    Background: Adrenomedullin (AM) and its receptor, receptor actvity-modifying protein (RAMP) 2 have pleiotropic regulatory functons in normal tssue and cancer tssue. AM is produced and secreted both numerous stromal cells and tumor cells. This study aims to investgate a possible role of AM and RAMP2 in the radiaton exposure in the normal lung tssue. M aterial s and Methods: Four groups with 6 male adult Swiss Albino mice per group were investgated. The mice were subjected to a 500 cGy single-dose radiaton exposure in the total body radiaton device and lung tssues were collected. 1, 2, and 7 days after radiaton exposure, with 1 reference group which was not exposed to radiaton. Results: The general histology and the immunohistochemistry of the tssue samples prepared with ant-AM, ant-RAMP2, and monoclonal antbodies were investgated, yielding a statstcally significant increase for AM on day 3 and for RAMP2 on day 1 after radiaton exposure. Conclusion: The observed increase of AM and RAMP2 concentratons in the normal tssue matrix after radiaton exposure may play a role in the side effects of radiotherapy. © 2020 Novin Medical Radiation Institute. All rights reserved.
  • No Thumbnail Available
    Item
    Mitophagy in the A549 lung cancer cell line, radiation-induced damage, and the effect of ATM and PARKIN on the mitochondria
    (Novin Medical Radiation Institute, 2022) Kurtman C.; Öztatlıcı M.; Üçöz M.; Çelik Ö.K.; Sokur I.; Özbilgin M.K.
    Background: Non-small cell lung cancer (NSCLC) is the most commonly diagnosed cancer, and radiotherapy (RT) is used for the cancer therapy. RT affects DNA and causes DNA double-strand breaks which are repaired by DNA repair protein ataxia telangiectasia mutated (ATM). RT also affects the mitochondria which is a key player in mediating the radiation response in tumors and removing damaged mitochondria through mitophagy. During mitophagy, PARKIN accumulates on defective mitochondria to mediate the clearance of damaged mitochondria. This study examines the effect of radiation on mitophagy using PARKIN and ATM antibodies on the human NSCLC A549 line. Materials and Methods: A549 cells were treated with 2, 4, 6 and 8 Gy of radiation were analyzed on days 1 and 3 after a single dose of radiotherapy. PARKIN and ATM expressions of A549 cells were examined by using immunohistochemical technique. Results: In the control groups, weak immunoreactivity of ATM and PARKIN was observed on both days 1 and 3. The most intense ATM expression was seen in the 6 and 8 Gy groups after day 1. The most intense PARKIN expression was seen after the days 1 and 3 in the 2 Gy groups. PARKIN immunoreactivity decreased due to increasing radiation dose. Conclusion: It must be considered that mitophagy mechanisms are activated in RT applications. It must be considered that the activation of mitophagy mechanisms in RT and A549 lung cancer cell lines may provide hemostasis in cancer cells. Molecules targeting mitophagy must be developed for use with radiotherapy. © 2022 Novin Medical Radiation Institute. All rights reserved.
  • No Thumbnail Available
    Item
    Determination of radioactivity levels and radiological risk factors in bozcaada-canakkale, turkey
    (Novin Medical Radiation Institute, 2024) Çam-Kaynar S.
    Background: Natural radiation is radiation that comes from two main environmental sources, the cosmic radiation from space that passes through the atmosphere, and terrestrial radiation is created when radionuclides decay in rock and soil. The most important radionuclides forming the natural radioactivity in terrestrial sources are 40K, 238U and 232Th. Material and Methods: In this study, 137Cs, 40K, 238U and 232Th activity levels were measured in samples taken from different parts of the island and beaches to determine the environmental radioactivity of Bozcada-Çanakkale using gamma spectrometry with a NaI(Tl) detector and radiation hazard indexes were calculated for soils. Results: Average activity concentrations of 40K, 238U, 232Th and 137Cs in soils were obtained as 427, 24, 31, and 29 Bqkg-1, respectively. The average activity values for 40K, 238U, 232Th and 137Cs in beach sands were determined to be 329, 23, 11 and 14 Bqkg-1, respectively. Radiological risk factors for Bozcaada soils were calculated. Conclusion: Our results were compared with the literature data and average world limit values. As a result of this study, we can state that the activity concentrations of Bozcaada Island beach sands are lower than the activity concentrations of soils. Since Bozcada is an island that attracts tourists, the low radionuclide activity in the beach sands shows that this place does not pose a significant radiological threat to peoples. © 2024 Novin Medical Radiation Institute. All rights reserved.