Assessment of cumulative radiation dose of neonate hospitalized in intensive care units

BACKGROUND AND OBJECTIVE: Newborns admitted to the neonatal intensive care unit (NICU), would be undergo a large number of X-ray imaging due to their involvement with various diseases The most important complication of receiving too much X-rays is an increased risk of various cancers. The aim of this study was to determine the average cumulative dose received by neonates admitted to the neonatal intensive care unit. METHODS: This cross-sectional study was performed on 20 neonates admitted to the intensive care unit of Taleghani Children's Hospital who were randomly selected. Infant information registrated including time of birth, arrival time, duration of hospitalization, age, sex, weight and number of radiographs performed on the infant and radiographic information including tube-to-patient distance, tube voltage (kVp) and milliamperes (mAs). The amount of skin absorption dose of each patient was evaluated using MTS700 thermoluminescence dosimeter and the number of imaging was examined. FINDINGS: The amount of entrance skin dose of the studied neonates with an average of 78 micrograys varied from 42 to 121 micrograys (78±19.6). The mean number of imaging and cumulative dose were 6 (6±7.71) and 521 micrograys (521±547.99), respectively. The highest cumulative dose (2106 μg) was related to a neonate who underwent 27 imaging. CONCLUSION: According to the results of this study, the need for multiple imaging of these infants can significantly increase their absorption dose, especially in infants with very low weight. © 2020, Babol University of Medical Sciences. All rights reserved

Corrigendum to �Three-dimensional film dosimetry of photon beam in small field sizes and beyond the heterogeneous regions using a GAFchromic films array� Radiat. Phys. Chem. 166 (2020) 108467 (Radiation Physics and Chemistry (2020) 166, (S0969806X19304335), (10.1016/j.radphyschem.2019.108467))

The name of one of the authors was misspelled in the article titled Three-dimensional film dosimetry of photon beam in small field sizes and beyond the heterogeneous regions using a GAFchromic films array on the date of 2020 submitted by me, Leili Mahani in the Radiation Physics and Chemistry journal. Is it possible to change �Milad Zeinali Kermani� to �Ahad Zeinali� and replace the item �e" with �c� in affiliations? The correct case will be as follows: Zahra Arab-Bafrania,b Leili Mahanic,d Alireza Khoshbin-Khoshnazara,b Ahad Zeinalic a Metabolic Disorders Research Center, Golestan University of Medical Sciences, Gorgan, Iran bDepartment of Biochemistry and Biophysics, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran cDepartment of Medical Physics, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran dDepartment of Radiation Oncology, Seyed Al-Shohada Hospital, Isfahan University of Medical Sciences, Isfahan, Iran. The authors would like to apologise for any inconvenience caused. © 2021 Elsevier Lt

Three dimensional film dosimetry of photon beam in small field sizes and beyond the heterogeneous regions using a GAFchromic films array

Introduction: Inaccurate dose prediction by treatment planning system (TPS) beyond the heterogeneous regions has been a great challenge in radiotherapy, particularly when small field sizes are used. Better understanding of this inaccuracy that depends on dosimetry methods is very crucial. Recently, the film stack dosimeter has been purposed for 3D comprehensive dosimetry. This study proposes an approach to investigate the accuracy of TPS for predicting dose distribution in small field sizes in the presence of nasopharynx heterogeneities by 3D stack film. Material & methods: The dose distribution and dose profile of rectangular heterogeneous nasopharynx (RHN) phantom with two air cavities and bone equivalent were measured with a 3D stack film dosimeter containing 9 GAFchromic-EBT2 films positioned beyond the heterogeneity regions. The film was validated using MCNPX-Monte Carlo (MC) simulation. The evaluation of TPS inaccuracy in small field sizes (3 � 3, 4 � 4, 5 � 5 cm2) was determined by comparing reconstructed 3D dose distribution of stack film dosimeter with TPS based on full scatter convolution (FSC) using in-house Matlab code. Results: The film measurements had a good agreement with the MC calculation for small fields in RHN phantom. The results showed a large discrepancy between stack film measurements and TPS calculations in the volumes enclosed high isodoses, so that the biggest difference occurred in 3 � 3 cm2 field size (relative mean difference = 1.72 ± 0.24, 1.5 ± 0.16 and P-value = 0.002, 0.001 for V95 and V90 respectively) and it decreased in 5 � 5 cm2 field size (relative mean difference = 0.46 ± 0.05, 0.35 ± 0.04 and P-value = 0.001, 0.002 for V95 and V90 respectively). Conclusion: The results suggested that 3D stack film dosimetry can be successfully used as a reliable dosimeter for QA procedure of heterogeneous region in small field sizes. Comparison of the measured and calculated dose volumes demonstrated that the TPS based FSC algorithm has a notable inaccuracy in estimation of dose distribution beyond the nasopharynx heterogeneities. Therefore: it seems heterogeneity corrections should be considered for nasopharynx treatment. © 2019 Elsevier Lt

Thyroid diseases: Pathophysiology and new hopes in treatment with medicinal plants and natural antioxidants

The thyroid gland regulates a wide range of physiological activities such as growth, metabolism, homeostasis, and cell proliferation and differentiation through the secretion of thyroid hormones (THs). Thyroid diseases are among the most common endocrine disorders, hypothyroidism is the most common clinical thyroid dysfunction. Hyperthyroidism means increased thyroid function and refers to excess metabolic state due to excessive synthesis and secretion of TH. Medicinal plants have been identified and used by humans throughout history. To name the herbs and natural antioxidants used to treat thyroid disorders including hypothyroidism and hyperthyroidism. Related articles were obtained using the Google Scholar, PubMed, and ScienceDirect databases. The results of this study indicate that medicinal plants include Fucus vesiculosus, Aegle marmelos, Coleus forskohlii, Linum usitatissimum, Withania somnifera, Commiphora mukul, Nigella sativa, and Bacopa monnieri. They can improve the hyperthyroidism in improving hyperthyroidism and herbal remedies, Melissa officinalis A. marmelos, Lycopus europaeus, Leonurus cardiaca, and Aloe barbadensis be effective. Herbal drugs cause comparatively fewer side effects. It is believed that the drugs derived from the plants are very safe and produce significant effects in the treatment of various diseases. Today, traditional medicine is being widely used and plants are still considered a major source of natural antioxidants that can serve as a clue for the development of new drugs. © 2018 BRNSS Publication Hub. All rights reserved

Changes in the radiation toxicity of human lymphoblastic t-cell line (Jurkat) by a common pesticide: Diazinon

Background: Diazinon is one of the most common pesticides in the world playing a similar role to radiation and it could cause DNA breaks and genetic effects. Objective: In this study, radiosensitivity of a lymphoblastic cell line pretreated by Diazinon was investigated. Material and Methods: In this case-control study, the human lymphoblastic T-cell line was divided into 6 groups based on receiving radiation or/and Diazinon. After that, the DNA damage, in all of the groups, were counted by cytokinesis-block micronuclei assay using different indices. Results: The mean frequency of micronuclei, nuclear bridges and nuclear buds in cell groups exposed by both Diazinon and radiation were remarkably higher than the other groups which just received radiation or Diazinon alone. The interaction between radiation and Diazinon treatment was statistically significant for NBUDS index. Conclusion: The results indicated that the Diazinon contamination could affect the radiosensitivity index of cancerous cells while further molecular and in-vivo studies are needed to investigate genetic and toxic effects of Diazinon on DNA and its repair system. © 2020, Shiraz University of Medical Sciences. All rights reserved

Enhanced radiotherapy efficacy of breast cancer multi cellular tumor spheroids through in-situ fabricated chitosan-zinc oxide bio-nanocomposites as radio-sensitizing agents

Overwhelming evidence has shown that three-dimensional multicellular tumor spheroids (MCTSs) as a mimic of in-vivo tumor can accurately exhibit cellular responses to treatments. So, we compared the capability of pure zinc oxide nanoparticles (ZnO-NPs) and chitosan-ZnO bio-nanocomposites (CS-ZnO BNCs) for enhancing the radiosensitization of MDA-MB-231 breast cancer cells (BCCs) in the 3D-MCTSs model. ZnO-NPs and CS-ZnO BNCs were synthesized by a facile co-precipitation method. FE-SEM images revealed that the uniform spherical ZnO-NPs with an average diameter of 35 nm were successfully dispersed on chitosan. MDA-MB-231 MCTSs which were formed in a non-adherent culture plate, possessed functional features of in-vivo tumor. The priority of such culture method to conventionally used 2D monolayer (or parental) cell culture is the mimicking of tumor microenvironment. The toxicity of CS-ZnO BNCs and ZnO-NPs against the MDA-M�231 BCCs was evaluated using MTT-colorimetric assay, which demonstrated superior biocompatibility of CS-ZnO BNCs compared to pure ZnO-NPs (even at high concentration of 100 μg/mL). Survival fraction analysis of cells under clinical X-ray irradiation (6 MV) showed that MCTSs had a higher radioresistance compared to parental cells. Besides, the clonogenic potential of irradiated MCTSs was significantly decreased by the addition of CS-ZnO BNCs similar to that of monolayer cells. The sensitivity enhancement ratios (SER) for MCTSs and monolayer cells were calculated 1.5 and 1.63, respectively. Further, tracking of radiobiological properties and apoptosis induction of MCTSs showed that CS-ZnO BNCs not only could lead to the creation of higher radiation-induced complex DNA break and apoptosis death in MCTSs, but also weakened DNA repair mechanisms. It was found that non-toxic concentration of CS-ZnO BNCs has promising potential to enhance radiosensitivity of resistant-MCTSs as a superior in-vitro tumor model. So, CS-ZnO BNCs can be a prominent candidate for overcoming the resistance of BCCs to radiotherapy. © 2021 Elsevier B.V