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Background: Osteoporosis is a systemic skeletal disease characterized by low bone mineral density (BMD) and micro-architectural deterioration of bone tissue, leading to bone fragility and increased fracture risk. Since Panoramic image is a feasible and relatively routine imaging technique in dentistry; it could provide an opportunistic chance for screening osteoporosis. In this regard, numerous panoramic derived indices have been developed and suggested for osteoporosis screening. Jaw trabecular pattern is one of the main bone strength factors and trabecular bone pattern assessment is important factor in bone quality analysis. Texture analysis applied to trabecular bone images offers an ability to exploit the information present on conventional radiographs. Objective: The purpose of this study was to evaluate the relationship between Jaw trabecular pattern in panoramic image and osteoporosis based on image texture analyzing using local binary pattern. Material and Methods: An experiment is evaluated in this paper based on a real hand-captured database of panoramic radiograph images from osteoporosis and non-osteoporosis person in Namazi Hospital, Shiraz, Iran .An approach is proposed for osteoporosis diagnosis consisting of two steps. First, modified version of local binary patterns is used to extract discriminative features from jaw panoramic radiograph images. Then, classification is done using different classifiers. Results: Comparative results show that the proposed approach provides classification accuracy about 99.6%, which is higher than many state-of-the-art methods. Conclusion: High classification accuracy, low computational complexity, multiresolution and rotation invariant are among advantages of our proposed approach.

Background: Electromagnetic fields (EMF) with different intensities are widely used at home, offices and public places.Today, there is a growing global concern about the effects of human exposure to EMFs. Epilepsy is one of the most common chronic neurological diseases, affecting 50 million people of all ages worldwide. We aimed to investigate the effect of exposure to Wi-Fi radiation on epileptic behavior of rats. Methods: 147 male rats, weighing 200-250 g, were divided into seven groups; negative control (no intervention), sham 1(distilled water), positive control (Pentylentetrazol [PTZ]), intervention group 1 (PTZ + Wi-Fi “off”), sham 2 (distilled water + Wi-Fi “off”), sham 3 (distilled water + Wi-Fi “on”), and intervention group 2 (PTZ + Wi-Fi “on”). The rats were exposed to Wi-Fi for 2h at a distance of 30cm from a commercial Wi-Fi router. Convulsive behaviors of rats were monitored and scored based on the intensity and type by measuring latency/threshold time, number of convulsions, sum of scores and durations of seizure, and duration of score 6 seizure. Kruskal-Wallis and Mann-Whitney U-tests were used to analyze the data. Results: Convulsion was observed in interventions Group 4 and Group 7, and positive control. The mean number of events, and sum of scores were significantly different in intervention 2 than other two groups. However, the differences in mean threshold, mean sum of durations and “ time to show convulsion with score 6 ” were not statistically significant (P>0.05). Conclusion: Due to limitations of our study including the sample size, these findings should be interpreted with caution. In this study, exposure to 2.4 GHz Wi-Fi radiation showed significant beneficial effects on the epileptic behaviour of rats. More experiments are needed to verify if these exposures can be used as a therapeutic approach for amelioration of seizures in epilepsy.

The aim of this report is to present a new two-piece thyroid-neck phantom produced by the concurrent use of epoxy resin and poly(methyl methacrylate) (PMMA: plexiglass) soft tissue equivalent materials. Accordingly, mass attenuation coefficients of the epoxy resin and the plexiglass compounds were obtained from simulation (NIST XCOM 3.1) and measurements (practical dosimetry) and compared to those related to human soft tissue (ICRU 44). The thyroid-neck phantom and thyroid gland dimensions were derived from scientific references and the atlas of human anatomy, respectively. The thyroid phantom was designed by CATIA V5R16 software and produced by the epoxy resin compound by three-dimensional printer. Other organs were designed by ProNest software and made by the plexiglass sheets by CNC laser cutting machine. The mass attenuation coefficients for the epoxy resin (50 keV- 20 MeV) and the plexiglass (0-20 MeV) were comparable to human soft tissue (ICRU 44), all with standard relative deviation beneath 5%. In addition, the SPECT images indicated the similarity between human thyroid tissue and its phantom. In conclusion, this study proves the feasibility and reliability of epoxy resin application in the production of two-piece thyroid-neck phantom. This phantom can be applied in the calibration of gamma camera systems, dosimetry and gamma spectrometry in the nuclear medicine field.

A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations after exposure to RF-EMFs have further supported these findings. Although the accelerated microleakage induced by RF-EMFs is clinically significant, the entire mechanisms of this phenomenon are not clearly understood. In this paper, we introduce “Triple M” effect, a new evidence-based theory which can explain the accelerated microleakage of dental amalgam fillings after exposure to different sources of electromagnetic radiation. Based on this theory, there are saliva-filled tiny spaces between amalgam and the tooth. Exposure of the oral cavity to RF-EMFs increases the energy of these small amounts of saliva. Due to the small mass of saliva in these tiny spaces, a small amount of energy will be required for heating. Moreover, reflection of the radiofrequency radiation on the inner walls of the tiny spaces causes interference which in turn produces some “hot spots” in these spaces. Finally, formation of gas bubbles in response to increased temperature and very rapid expansion of these bubbles will accelerate the microleakage of amalgam. Experiments that confirm the validity of this theory are discussed.

Background: A new treatment approach for most patients who have undergone early stage non-small-cell lung carcinoma (NSCLC) is wedge resection plus permanent implant brachytherapy. However, the specification of dose to medium at low energies especially in heterogeneous lung is unclear yet. Objective: The present study aims to modify source strength for different configurations of 125I and 103Pd seeds used in lung permanent implant brachytherapy. Methods: Different arrays of 125I and 103Pd seeds were simulated by MCNPX code in protocol-based water vs. actual 3D lung environments. Absorbed dose was, then, scored in both mediums. Dose differences between both environments were calculated and source strength was modified for the prescription point. In addition, lung-towater absorbed dose ratio was obtained and presented by precise equations. Results: Due to significant differences in prescription dose, source strength was modified 16%-19% and 37%-43% for different configurations of 125I and 103Pd seeds, respectively. In addition, depth-dependent dose differences were observed between the actual lung and protocol-based water mediums (dose difference as a function of depth). Conclusion: Modification of source strength is essential for different arrangements of 125I and 103Pd seeds in lung implantation. Modified source strength and presented equations are recommended to be considered in future studies based on lung brachytherapy.

Background: A new treatment approach for most patients who have undergone early stage non-small-cell lung carcinoma (NSCLC) is wedge resection plus permanent implant brachytherapy. However, the specification of dose to medium at low energies especially in heterogeneous lung is unclear yet. Objective: The present study aims to modify source strength for different configurations of 125I and 103Pd seeds used in lung permanent implant brachytherapy. Methods: Different arrays of 125I and 103Pd seeds were simulated by MCNPX code in protocol-based water vs. actual 3D lung environments. Absorbed dose was, then, scored in both mediums. Dose differences between both environments were calculated and source strength was modified for the prescription point. In addition, lung-towater absorbed dose ratio was obtained and presented by precise equations. Results: Due to significant differences in prescription dose, source strength was modified 16%-19% and 37%-43% for different configurations of 125I and 103Pd seeds, respectively. In addition, depth-dependent dose differences were observed between the actual lung and protocol-based water mediums (dose difference as a function of depth). Conclusion: Modification of source strength is essential for different arrangements of 125I and 103Pd seeds in lung implantation. Modified source strength and presented equations are recommended to be considered in future studies based on lung brachytherapy. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance effect of gold nanostructures makes them good candidates for photothermal therapy (PTT) application. Herein, gold-ferrite nanocomposite (GFNC) was synthesized and characterized as a photothermal agent in PTT. The aim of this study was to investigate the effect of GFNC upon laser irradiation on treatment of cancer in mice bearing melanoma cancer. Thirty mice received 1.5 × 10(6) B16/F10 cells subcutaneously. After 1 week, the mice bearing solid tumor were divided into four groups: control group (without any treatment), laser group (received laser irradiation without GFNC injection), GFNC group (only received intratumorally GFNC), and GFNC + laser group (received intratumorally GFNC upon laser irradiation). In GFNC + laser group, 200 μL of fluid, 1.3 × 10(-7) mol L(-1) gold nanoparticles, was injected intratumorally and immediately the site of tumor was exposed to continuous wave diode laser beam (808 nm, 1.6 W cm(-2)) for 15 min. All mice but four were euthanized 24 h after treatment to compare the necrotic surface area histologically by using measuring graticule. Statistical analyses revealed significant differences in necrosis extent for GFNC + laser group, compared to other groups. Four subjects (control group and GFNC + laser group, two mice each) were kept for longitudinal study. Histological analyses and tumor volume measurements of the four subjects indicated that tumor in GFNC + laser group was controlled appropriately. It was concluded that combining an 808-nm laser at a power density of 1.6 W cm(-2) with GFNC has a destruction effect in melanoma cancer cells in an animal model. [ABSTRACT FROM AUTHOR]

Background: Nowadays, mothers are continuously exposed to different sources of electromagnetic fields before and even during pregnancy. It has recently been shown that exposure to mobile phone radiation during pregnancy may lead to adverse effects on the brain development in offspring and cause hyperactivity. Researchers have shown that behavioral problems in laboratory animals which have a similar appearance to ADHD are caused by intrauterine exposure to mobile phones. Objective: The purpose of this study was to investigate whether the maternal exposure to different sources of electromagnetic fields affect on the rate and severity of speech problems in their offspring. Methods: In this study, mothers of 35 healthy 3-5 year old children (control group) and 77 children and diagnosed with speech problems who had been referred to a speech treatment center in Shiraz, Iran were interviewed. These mothers were asked whether they had exposure to different sources of electromagnetic fields such as mobile phones, mobile base stations, Wi-Fi, cordless phones, laptops and power lines. Results: We found a significant association between either the call time (P=0.002) or history of mobile phone use (months used) and speech problems in the offspring (P=0.003). However, other exposures had no effect on the occurrence of speech problems. To the best of our knowledge, this is the first study to investigate a possible association between maternal exposure to electromagnetic field and speech problems in the offspring. Although a major limitation in our study is the relatively small sample size, this study indicates that the maternal exposure to common sources of electromagnetic fields such as mobile phones can affect the occurrence of speech problems in the offspring. [ABSTRACT FROM AUTHOR]

The author reflects on the complexities and importance of ethical issues facing editors of the "Journal of Biomedical Physics & Engineering."

Background: Radiotherapy has become a part of therapeutic process of more than 50 percent of patients suffering from cancer. However, recent studies have shown that radiation therapy might affect the expression of adhesive molecule related genes such as E-cadherin and cause cancer cells to move and migrate. Besides, various studies have reported that the expression of E-cadherin changes differently after radiation treatment. There are several studies which showed the loss of E-cadherin function after radiation; however, this reduction has not been observed in others., Objective: This study aims to investigate the effect of different radiation doses of X-ray on changes that might occur in the expression of E-cadherin gene in colorectal cancer cell line HT-29., Material and Methods: In this experimental study, the cells cultured in flasks were irradiated with X- rays in different doses, including 0.1, 2.5, 5, and 10 Gy; then, the expression of E-cadherin gene was measured using real-time PCR., Results: The expression of E-cadherin did not change significantly in post-irradiated HT-29 cell line after different radiation doses of X-ray., Conclusion: The results showed that low, medium and high doses of X- radiation did not change the expression of E-cadherin gene in HT-29 cancer cells. However, it has been reported that radiation mostly downregulated the expression of E-cadherin and mediated metastasis formation and invasiveness in different cancer cell lines. Therefore, further studies need to be conducted to investigate the effects of radiation dose on the molecular pathways contributing to regulation of E-cadherin in HT-29 cell line., (Copyright: © Journal of Biomedical Physics and Engineering.)

Background: A new treatment approach for most patients who have undergone early stage non-small-cell lung carcinoma (NSCLC) is wedge resection plus permanent implant brachytherapy. However, the specification of dose to medium at low energies especially in heterogeneous lung is unclear yet., Objective: The present study aims to modify source strength for different configurations of 125I and 103Pd seeds used in lung permanent implant brachytherapy., Methods: Different arrays of 125 I and 103 Pd seeds were simulated by MCNPX code in protocol-based water vs. actual 3D lung environments. Absorbed dose was, then, scored in both mediums. Dose differences between both environments were calculated and source strength was modified for the prescription point. In addition, lung-to-water absorbed dose ratio was obtained and presented by precise equations., Results: Due to significant differences in prescription dose, source strength was modified 16%-19% and 37%-43% for different configurations of 125 I and 103 Pd seeds, respectively. In addition, depth-dependent dose differences were observed between the actual lung and protocol-based water mediums (dose difference as a function of depth)., Conclusion: Modification of source strength is essential for different arrangements of 125 I and 103 Pd seeds in lung implantation. Modified source strength and presented equations are recommended to be considered in future studies based on lung brachytherapy.

Application of superparamagnetic iron oxide nanoparticles (NPs) as a negative contrast agent in magnetic resonance imaging (MRI) has been of widespread interest. These particles can enhance contrast of images by altering the relaxation times of the water protons. In this study, dextrin-coated zinc substituted cobalt-ferrite (Zn0.5Co0.5Fe2O4) NPs were synthesized by a co-precipitation method, and the morphology, size, structure and magnetic properties of the NPs were investigated. These NPs had superparamagnetic behavior with an average size of 3.9 (±0.9, n=200)nm measured by transmission electron microscopy. Measurements on the relaxivities (r2 and r2(*)) of the NPs were performed in vitro by agarose phantom. In addition, after subcutaneous injection of the NPs into C540 cell line in C-57 inbred mice, the relaxivities were measured in vivo by a 1.5T MRI system. These NPs could effectively increase the image contrast in both T2-and T2(*)-weighted samples., (Copyright © 2015 Elsevier B.V. All rights reserved.)