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Background: It is essential to evaluate the accuracy of dose calculation for treatment planning systems (TPSs). This study's primary goal was to evaluate the accuracy of dose calculation for ISOgray TPS in the presence of a wedges in the treatment fields. Materials and Methods: GATE (Geant4 Application for Tomography Emission) as a Monte Carlo (MC) code was utilized to model the 6 MV photon beam of an Elekta Compact linac. It did MC code verification for three different field sizes and three depths for open, and wedged fields with gamma index tool. Following the confirmation, the percentage depth dose (PDD) and dose profile were calculated using the TPS and compared with the simulation results. In the next step, the TPS dose calculations for the 10×10cm2 field with different wedge angles were compared by the result from analytical formula. Results: The PDD and dose profiles for open fields met the gamma index criteria. However, there was disagreement for large wedged fields. The dose profiles of wedge angles using Petti analytical equation were compared to ISOgray dose profiles. Results showed that dose profile points with all wedge angles meet the gamma index criteria except for the 45° wedge angle. Conclusions: The results indicated that the disagreement between MC and TPS dose calculations increases by increasing wedge angle and field size. The uncertainty is due to TPS dose calculation algorithm causing noticeable disagreement. A MC-based TPS for dose calculation is recommended to reduce the error in dose calculation or at least medical physicist consider this issue. [ABSTRACT FROM AUTHOR]

Background: Given the importance of scattered and low doses in secondary cancer caused by radiation treatment, the point dose of critical organs, which were not subjected to radiation treatment in breast cancer radiotherapy, was measured. Objective: The purpose of this study is to evaluate the peripheral dose in two techniques of breast cancer radiotherapy with two energies. Material and Methods: Eight different plans in two techniques (conventional and conformal) and two photon energies (6 and 15 MeV) were applied to Rando Alderson Phantom’s DICOM images. Nine organs were contoured in the treatment planning system and specified on the phantom. To measure the photon dose, fortyeight thermoluminescence dosimeters (MTS700) were positioned in special places on the above nine organs and plans were applied to Rando phantom with Elekta presice linac. To obtain approximately the same dose distribution in the clinical organ volume, a wedge was used on planes with an energy of 6 MeV photon. Results: Point doses in critical organs with 8 different plans demonstrated that scattering in low-energy photon is greater than high-energy photon. In contrast, neutron contamination in high-energy photon is not negligible. Using the wedge and shield impose greater scattering and neutron contamination on patients with low-and high-energy photon, respectively. Conclusion: Deciding on techniques and energies required for preparing an acceptable treatment plan in terms of scattering and neutron contamination is a key issue that may affect the probability of secondary cancer in a patient.

Background and Objective: Failure to follow the standard guidelines in the selection and monitoring of infants before and during home phototherapy can result in unfavorable outcomes. The present study was conducted to determine the performance and complications of failure to follow the standard guidelines in infants undergoing home phototherapy in Mashhad, Iran. Methods: In this cross-sectional study, a total of 202 infants who were referred to neurology clinic or hospitalized at the emergency or neonatal wards due to acute or chronic outcomes of home phototherapy were included in 2020-2021. Gestational age, gender, birth weight, age at jaundice onset, age and duration of phototherapy, weight on admission, etiology of jaundice, referrer, phototherapy service providing center, type of breastfeeding, hyperthermia incidence, serum or skin bilirubin levels at the beginning and end of phototherapy, hematocrit, direct and indirect Coombs test, reticulocyte count, TSH, T4, G6PD, maternal age and blood type, parity, type of delivery, and pregnancy and delivery problems were recorded. Findings: The mean age of infants was 7.7±7.6 days, birth weight 2746±707 gr, admission weight 2601±771, bilirubin before home phototherapy 15.58±3.7 mg/dl, bilirubin on admission 17.5±5.8 mg/dl, and home phototherapy duration was 2.5±0.7 days. The frequency of causes of jaundice was as follows: ABO incompatibility (n=30), Rh incompatibility (n=22), urinary tract infections (n=13), fever and dehydration (n=19), hypothyroidism (n=7), biliary atresia (n=5), galactosemia (n=2), and etc. Thirty infants had pathologic weight loss, six had kernicterus, and three needed exchange transfusion. Conclusion: According to the findings of the present study, it seems that the non-compliance with the guidelines and standards for the selection of babies eligible for home phototherapy along with the lack of monitoring of the health status and serum bilirubin of these infants lead to serious consequences (dehydration and pathological weight loss, need for exchange transfusion and kernicterus) in them. It is necessary to closely review and monitor the process of diagnosis and referral of babies with jaundice who need phototherapy and treatment to phototherapy centers at home or hospital. [ABSTRACT FROM AUTHOR]

Introduction: Organ dose distribution calculation in radiotherapy and knowledge about its side effects in cancer etiology is the most concern for medical physicists. Calculation of organ dose distribution for breast cancer treatment plans with Monte Carlo (MC) simulation is the main goal of this study., Materials and Methods: Elekta Precise linear accelerator (LINAC) photon mode was simulated and verified using the GEANT4 application for tomographic emission. Eight different radiotherapy treatment plans on RANDO's phantom left breast were produced with the ISOgray treatment planning system (TPS). The simulated plans verified photon dose distribution in clinical tumor volume (CTV) with TPS dose volume histogram (DVH) and gamma index tools. To verify photon dose distribution in out-of-field organs, the point dose measurement results were compared with the same point doses in the MC simulation. Eventually, the DVHs for out-of-field organs that were extracted from the TPS and MC simulation were compared., Results: Based on the implementation of gamma index tools with 2%/2 mm criteria, the simulated LINAC output demonstrated high agreement with the experimental measurements. Plan simulation for in-field and out-of-field organs had an acceptable agreement with TPS and experimental measurement, respectively. There was a difference between DVHs extracted from the TPS and MC simulation for out-of-field organs in low-dose parts. This difference is due to the inability of the TPS to calculate dose distribution in out-of-field organs., Conclusion and Discussion: Based on the results, it was concluded that the treatment plans with the MC simulation have a high accuracy for the calculation of out-of-field dose distribution and could play a significant role in evaluating the important role of dose distribution for second primary cancer estimation., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Medical Signals & Sensors.)

The emergence of multidrug resistance in bacterial infections has limited the use of antibiotics. Helping the action of antibiotics is one of the needs of the day. Today, the biosynthesis of nanoparticles (NPs) is considered due to its safety and cost-effectiveness. In this study, we investigated the effect of biosynthesized silver nanoparticles (AgNPs) by Berberine plant extract against standard strains of multidrug-resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa . Utilized UV-Vis, FTIR, FESEM/EDX, XRD, DLS, and Zeta potential techniques to confirm the biosynthesis of NPs. Then, disk diffusion agar (DDA) and minimum inhibitory concentration (MIC) tests were performed using common classes of standard antibiotics and AgNPs on the mentioned bacteria. The synergistic action between AgNPs and antibiotics was evaluated by the checkerboard method. First, we obtained the confirmation results of the biosynthesis of AgNPs. According to the DDA test, both standard bacterial strains were sensitive to NPs and had an inhibition zone. Also, the MIC values showed that AgNPs inhibit the growth of bacteria at lower concentrations than antibiotics. On the other hand, the results obtained from checkerboard monitoring showed that AgNPs, in combination with conventional antibiotics, have a synergistic effect. The advantage of this study was comparing the antibacterial effect of AgNPs alone and mixed with antibiotics. The antibacterial sensitivity tests indicated that the desired bacterial strains could not grow even in low concentrations of AgNPs. This property can be applied in future programs to solve the drug resistance of microorganisms in bacterial diseases., Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01136-y., Competing Interests: Competing interestThe authors declare no conflict of interest., (© Association of Microbiologists of India 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

This study aims to investigate the levels of receptor-binding domain (RBD), spike, and neutralizing antibodies in pregnant women who received the Sinopharm vaccine and their newborns. A cross-sectional study was conducted at a tertiary center, Mashhad, Iran. We included 88 pregnant women who had received at least two doses of the Sinopharm vaccine. Maternal and umbilical cord blood samples taken at delivery were analyzed for antibodies using ELISA tests. Antibody levels did not vary significantly between women with two or three vaccine doses. Only 1.1% of mothers had undetectable levels of RBD antibodies, but detectable antibodies were observed in all newborns. A significant linear correlation was found between the levels of neutralizing antibodies (r = 0.7, p < 0.001) and RBD antibodies (r = 0.833, p < 0.001) in mothers and their newborns, but not for Spike antibodies (r = 0.214, p = 0.045). In mothers, high titers of antispike and RBD antibodies were observed at the time of delivery. The high titers of RBD and antispike antibodies were found in cord blood, suggesting potential neonatal immunity. Detectable levels of antibodies were found in both groups, regardless of the timing of vaccination. The Sinopharm vaccine generates detectable levels of antibodies in pregnant women, which are efficiently transferred to their newborns. The number of vaccine doses (two or three) did not significantly impact the levels of detectable antibodies. This underscores Sinopharm's potential efficacy in protecting pregnant women and their infants from COVID-19., (© 2023 Wiley Periodicals LLC.)

The problems of drug resistance in bacteria have become one of the daily challenges of the clinical treatment of patients, which inevitably forces us to use agents other than common antibiotics. Among these, we can take help from different properties and applications of nanoparticles (NPs). In this work, we evaluate the antibacterial activity of biosynthesized selenium nanoparticles (SeNPs) against standard strains of multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii. The production of biosynthesized SeNPs was proved by ultraviolet-visible, Fourier transform infrared, X-ray diffractometer, Field Emission Scanning Electron Microscopy, Dynamic light scattering, and Zeta potential methods. The cytotoxicity effect of SeNPs was investigated by MTT assay. Disk diffusion agar (DDA) and minimum inhibitory concentration (MIC) tests were performed on the mentioned bacteria using different classes of standard antibiotics and SeNPs separately. The impact of SeNPs combined with the desired antibiotics for better treatment of these infections was evaluated by checkerboard assay to determine the synergism effect. After the confirmation results based on the biosynthesis of SeNPs, both standard bacterial strains were susceptible to SeNPs and had a zone of inhibition using the DDA test. Also, the results of MICs showed that biosynthesized SeNPs in lower concentrations than antibiotics cause no growth of bacteria. On the other hand, according to the checkerboard assay, SeNPs had a synergistic effect with conventional antibiotics. The antibacterial sensitivity tests demonstrated the inhibition of bacterial growth in the presence of lower concentrations of SeNPs than common antibiotics. This property can be exerted in future applications to solve the drug resistance obstacle of microorganisms in bacterial diseases., (© 2022 Wiley-VCH GmbH.)

Background: Curcumin, a natural polyphenolic compound, is proposed as a potential treatment option for patients with coronavirus disease by inhibiting the entry of virus to the cell, encapsulation of the virus and viral protease, as well as modulating various cellular signaling pathways. In this study, the efficacy and safety of nanocurcumin oral formulation has been evaluated in patients with mild-moderate Coronavirus disease 2019 (COVID-19) in outpatient setting., Methods: In this triple-blind randomized placebo-controlled clinical trial, sixty mild to moderate COVID-19 patients in outpatient setting who fulfilled the inclusion criteria were randomly allocated to treatment ( n  = 30) group to receive oral nanocurcumin formulation (Sinacurcumin soft gel which contains 40 mg curcuminoids as nanomicelles), two soft gels twice a day after food for 2 weeks or placebo ( n  = 30) group. Patients' symptoms and laboratory data were assessed at baseline and during follow-up period and compared between two groups., Results: All symptoms except sore throat resolved faster in the treatment group and the difference was significant for chills, cough and smell and taste disturbances. The CRP serum level was lower in the treatment group at the end of two weeks and the lymphocyte count was significantly higher in treatment group. No significant adverse reaction reported in the treatment group., Conclusion: Oral nanoformulation of curcumin can significantly improve recovery time in patients with mild to moderate COVID-19 in outpatient setting. Further studies with larger sample size are recommended., Competing Interests: Dr Mahmoud Reza Jaafari, one of the manuscript authors, is the founder of Exir Nano Sina Company. Other authors have nothing to declare. The study conforms to the Declaration of Helsinki, US, and/or European Medicines Agency Guidelines for human subjects., (© 2021 The Authors. Food Science & Nutrition published by Wiley Periodicals LLC.)

The main purpose of this study is to measure the contribution of the thermal and fast neutron dose along the central axis of the 15 MV Elekta Precise linac in a tissue equivalent phantom. In order to achieve this purpose, different points were selected in three field sizes of 5 × 5 cm2, 10 × 10 cm2 and 15 × 15 cm2. Fast and thermal neutrons were measured using CR-39 nuclear track detectors with and without thermal neutron converter of 10B, respectively. According to the results, the fast neutron dose equivalent was decreased as the depth increased (field size 5 × 5, 10 × 10 and 15 × 15 cm2 fall from 0.35 to 0.15, 0.5 to 0.3 and 0.5 to 0.3, respectively). Thermal dose equivalent was increased as the depth increased in the tissue equivalent phantom (field size 5 × 5, 10 × 10 and 15 × 15 cm2 rise from 0.1 to 0.4, 0.4 to 0.8 and 0.4 to 0.9, respectively). In conclusion, at depth <3 cm, most existing neutrons are fast and CR-39 films are sensitive to fast neutrons; therefore, they are more appropriate than thermoluminescent dosemeters in measuring neutron dose equivalent., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Aim: The main purpose of this study is to evaluate the effect of dose perturbation due to common dental restoration materials in the head and neck radiotherapy with a 15 MV external photon beam., Setting and Design: Teeth with three dental restorations such as tooth filled with Amalgam, Ni-Cr alloy, and Ceramco were simulated by MCNPX Monte Carlo code. In this simulation, the dental materials were exposed by a 15 MV photon beam from a Siemens Primus linac, inside a water phantom., Materials and Methods: A Siemens Primus linear accelerator and a phantom including: tooth only, tooth with Amalgam, tooth with Ni-Cr alloy, and tooth with Ceramco were simulated by MCNPX Monte Carlo code, separately. The percentage dose change was evaluated relative to dose in water versus depth for these samples on the beam's central axis. The absolute dose by prescription of 100 cGy dose in water phantom at 3.0 cm depth was calculated for water, tooth, tooth with Amalgam, tooth with Ni-Cr alloy, and tooth with Ceramco., Results: The maximum percentage dose change is related to tooth with Ni-Cr alloy, tooth, tooth with Ceramco, and tooth with Amalgam with amounts of 7.73%, 6.95%, 4.7%, and 3.06% relative to water at 0.75 cm depth, respectively. When 100.0 cGy dose was prescribed at 3.1 cm, the maximum absolute dose was 201.0% in the presence of tooth with Ni-Cr alloy at 0.75 cm., Conclusion: Introduction of the compositions of dental restorations can improve the accuracy of dosimetric calculations in treatment planning and protect the healthy tissues surrounding teeth from a considerable overdose., Competing Interests: None

The present study was performed to evaluate the clinical symptoms and cardiovascular complications in patients with typical and atypical Kawasaki disease (KD). This retrospective study was conducted on the medical records of 176 patients with KD for three years. The study population was divided into two groups of typical and atypical based on the KD clinical criteria. The two groups were compared in terms of demographic data, clinical symptoms, cardiac lesions, and laboratory markers. Based on the diagnostic criteria, 105 (60%) and 71 (40%) patients were diagnosed with typical and atypical KD, respectively. The mean age of the typical patients (38.16 months) was higher than that of the atypical group (24.03 months) at the time of diagnosis ( p < 0.05). The results revealed no significant difference between the two groups regarding the seasonal distribution of KD onset ( p = 0.422). However, the most common season for the diagnosis of the disease was spring, followed by winter. There was no significant difference between the two groups in terms of fever duration ( p = 0.39). Furthermore, vomiting was more common in the atypical patients than in the typical group ( p = 0.017). In terms of the cardiac lesions, ectasia ( p = 0.005) and lack of tapering of the distal coronary vessels ( p = 0.015) were more frequently detected in the atypical group than in the typical group. Considering the laboratory findings, thrombocytosis ( p = 0.010) and anemia ( p = 0.048) were more common in the atypical group, compared to those in the typical group. On the other hand, the typical group had a higher serum alanine aminotransferase level (adjusted for age) ( p = 0.012) and Hyponatremia (serum sodium concentration ≤130 mmol/L) ( p = 0.034). Based on the findings of the current study, the fever duration from onset to diagnosis was slightly more in atypical KD patients than in the typical group, but not statistically significant, possibly due to more timely diagnosis of atypical KD. There was no difference in coronary aneurysm between the two groups at the time of diagnosis. The atypical group had a higher frequency of coronary ectasia and lack of tapering, indicating cardiac involvement. Consequently, these conditions should be given more attention in the atypical patients. Furthermore, the higher frequency of anemia and thrombocytosis in the atypical patients can be useful for diagnosis of this kind of KD.

The CSM40 137 Cs source model is currently being used in clinical brachytherapy. According to the recommendations of task group No. 43 (TG-43) of the American Association of Physicists in Medicine, dosimetry parameters of brachytherapy sources should be determined by two independent investigators before their clinical use. The aim of this study was to determine the TG-43 dosimetry parameters for a medium-dose-rate CSM40 137 Cs source. The determined dosimetric parameters included the air kerma strength, dose rate constant, radial dose function, and anisotropy function. To determine the source's dosimetric parameters, the CSM40 source was stimulated by the Monte Carlo N-Particle MCNP code. The TG-43 parameters were compared with the data of Vijande et al. on this source. The results showed that the dosimetry parameters for this source had good agreement with the results of Vijande et al. The dosimetric parameters of the CSM40 source can be used in treatment-planning systems incorporating this source model. The data can also be used for the quality assurance of treatment-planning systems.

Aim: The purpose of this work is to evaluate the dosimetric parameters of a hypothetical (153)Gd source for use in brachytherapy and comparison of the dosimetric parameters with those of (192)Ir and (125)I sources., Materials and Methods: Dose rate constant, the radial dose function and the two dimensional (2D) anisotropy function data for the hypothetical (153)Gd source were obtained by simulation of the source using MCNPX code and then were compared with the corresponding data reported by Enger et al. A comprehensive comparison between this hypothetical source and a (192)Ir source with similar geometry and a (125)I source was performed as well., Results: Excellent agreement was shown between the results of the two studies. Dose rate constant values for the hypothetical (153)Gd, (192)Ir, (125)I sources are 1.173 cGyh(-1) U(-1), 1.044 cGyh(-1) U(-1), 0.925 cGyh(-1) U(-1), respectively. Radial dose function for the hypothetical (153)Gd source has an increasing trend, while (192)Ir has more uniform and (125)I has more rapidly falling off radial dose functions. 2D anisotropy functions for these three sources indicate that, except at 0.5 cm distance, (192)Ir and (125)I have more isotropic trends as compared to the (153)Gd source., Conclusion: A more uniform radial dose function, and 2D anisotropy functions with more isotropy, a much higher specific activity are advantages of (192)Ir source over (153)Gd. However, a longer half-life of (153)Gd source compared to the other two sources, and lower energy of the source with respect to (192)Ir are advantages of using (153)Gd in brachytherapy versus (192)Ir source.

Several investigators have pointed out that electron and neutron contamination from high-energy photon beams are clinically important. The aim of this study is to assess electron and neutron contamination production by various prostheses in a high-energy photon beam of a medical linac. A 15 MV Siemens PRIMUS linac was simulated by MCNPX Monte Carlo (MC) code and the results of percentage depth dose (PDD) and dose profile values were compared with the measured data. Electron and neutron contaminations were calculated on the beam's central axis for Co-Cr-Mo, stainless steel, Ti-alloy, and Ti hip prostheses through MC simulations. Dose increase factor (DIF) was calculated as the ratio of electron (neutron) dose at a point for 10 × 10 cm² field size in presence of prosthesis to that at the same point in absence of prosthesis. DIF was estimated at different depths in a water phantom. Our MC-calculated PDD and dose profile data are in good agreement with the corresponding measured values. Maximum dose increase factor for electron contamination for Co-Cr-Mo, stainless steel, Ti-alloy, and Ti prostheses were equal to 1.18, 1.16, 1.16, and 1.14, respectively. The corresponding values for neutron contamination were respectively equal to: 184.55, 137.33, 40.66, and 43.17. Titanium-based prostheses are recommended for the orthopedic practice of hip junction replacement. When treatment planning for a patient with hip prosthesis is performed for a high-energy photon beam, attempt should be made to ensure that the prosthesis is not exposed to primary photons.