Investigation the Effect of Low, Medium and High Dose of X-Radiation on the Expression of E-cadherin in Colorectal Cancer Cell Line.

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.

Mandibular Trabecular Bone Analysis Using Local Binary Pattern for Osteoporosis Diagnosis.

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, multi-resolution and rotation invariant are among advantages of our proposed approach.

Design and Production of Two-piece Thyroid-neck Phantom by the Concurrent Use of Epoxy Resin and Poly(methyl methacrylate) Soft Tissue Equivalent Materials.

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.

"Triple M" Effect: A Proposed Mechanism to Explain Increased Dental Amalgam Microleakage after Exposure to Radiofrequency Electromagnetic Radiation.

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.

Modification of Source Strength in Low-Dose-Rate Lung Brachytherapy with 125I and 103Pd Seeds.

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-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 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.

Photothermal cancer therapy by gold-ferrite nanocomposite and near-infrared laser in animal model.

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.

A Challenging Issue in the Etiology of Speech Problems: The Effect of Maternal Exposure to Electromagnetic Fields on Speech Problems in the Offspring.

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.

Dextrin-coated zinc substituted cobalt-ferrite nanoparticles as an MRI contrast agent: In vitro and in vivo imaging studies.

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.

Numerical investigation of angulation effects in stenosed renal arteries.

BACKGROUND: Numerical study of angulation effects of renal arteries on blood flow has been of great interest for many researchers. Objective : This paper aims at numerically determining the angulation effects of stenosed renal arteries on blood flow velocity and renal mass flow. METHOD: An anatomically realistic model of abdominal aorta and renal arteries is reconstructed from CT-scan images and used to conduct numerical simulation of pulsatile non-Newtonian blood flow incorporating fluid-structure interaction. The renal arteries in the realistic model have left and right branch angles of 53˚ and 45˚, respectively. Atrapezium shape stenosis is considered in the entrance of right renal artery. Two other branch angles, i.e. 90 and 135˚, are also considered for right renal artery to study the angulation effects. RESULTS: Comparison between models with right renal branch angles of 45˚, 90˚ and 135˚ reveals that high curvature of streamlines in the entrance of the renal artery with the angle of 135˚ causes the flow velocity and renal mass flow to be less than those of 45˚and 90˚. CONCLUSION: It is concluded that large renal branch angles cause the arteries to be unable to deliver blood in the requisite amounts to kidney. Kidney responds to counteract low blood flow by activating the renin-angiotension system which leads to severe hypertension.

Burnout in hospital nurses: a comparison of internal, surgery, psychiatry and burns wards.

INTRODUCTION: Burnout is a phenomenon in which the cumulative effects of a stressful work environment gradually overwhelm the defenses of staff members, forcing them to withdraw psychologically. This study compared the levels of burnout among nurses in different nursing specialties. MATERIALS AND METHODS: The sample of the study consisted of all the nurses working in all public hospitals in Shiraz, Iran who were graduates of either technological educational institutions or universities and had experienced clinical nursing practice for at least 1 year. Using Maslach Burnout Inventory and General Health Questionnaire (28-item version), we identified the psychiatric morbidity and burnout among nurses. RESULTS: Study results indicated that nurses of psychiatry wards showed significantly higher levels of emotional exhaustion and depersonalization in comparison with nurses working in other wards, and burn wards nurses showed significantly higher levels of personal accomplishment. Also, nurses who were single were more emotionally exhausted. CONCLUSION: Different clinical working environments appear to have an impact on the development of nurses' burnout.

Effect of hypertension on transplant kidney function: three year of follow-up.

BACKGROUND: Hypertension significantly increases the risk for chronic graft loss and accelerates the deterioration of transplanted kidney function. Aggressive control of blood pressure (BP) is recommended in the posttransplant period when maintenance levels of immunosuppressive drugs are achieved. The aim of this study was to investigate whether the improved control improved the graft survival. METHODS: We compared transplant kidney function in two groups of hypertensive patients matched for age, gender, donor-recipient relation, primary disease, early posttransplant course, and immunosuppressant and hypertensive therapy during 3 years follow-up. The patients were divided into satisfactory and unsatisfactory controlled blood pressure. Group 1 consisted of 98 patients with satisfactory BP control (arterial pressure <160/90 mmHg) and group 2, 98 patients with unsatisfactory BP control. RESULTS: The mean through levels of cyclosporine in whole blood were similar in both groups and did not exceed 185 ng/mL. A slow but significant increase in mean creatinine levels was observed among group 2 during 3 years follow-up, whereas, among group 1, graft function remained stable. Cardiovascular events were observed only in group 2: stroke in one patient and death because of heart failure in one patient. Factors which correlated with development of post transplant hypertension were age, gender, duration of disease before transplant, and underlying disease. CONCLUSION: Lowering BP, even several years posttransplantation, was associated with improved graft and patient survival in renal transplant recipients.

How to decrease cardiovascular mortality in renal transplant recipients.

Cardiovascular disease is the leading cause of death following renal transplantation, accounting for 40% to 55% of all deaths. An analysis in our center showed a 15% mortality in a cohort of renal transplant recipients followed for an average of 10 years. Various contributing risk factors of cardiovascular diseases in transplant recipients such as tobacco use, hypertension, hyperlipidemia, hereditary risk, diabetes, physical inactivity, obesity, dialysis duration, hyperuricemia, proteinuria, hyperhomocysteinemia, hyperparathyroidism, anemia; C-reactive protein level, and immunosuppressive regimen as well as some rare risk factors, such as cytomegalovirus infection, were evaluated in a population of 1200 kidney transplant recipients. Also we introduced methods for early detection, monitoring, and follow-up of proven risk factors of cardiovascular disease.

Predictors of cardiovascular events and associated mortality of kidney transplant recipients.

BACKGROUND: Cardiovascular disease is the most common cause of death after renal transplantation. Furthermore, acute coronary syndrome (ACS) attributable to coronary artery disease (CAD) accounts for the majority of deaths due to cardiovascular disease posttransplant. Although renal transplantation is the treatment of choice for end-stage renal disease, understanding the causes of graft and patient loss is exceedingly important to improve outcomes. METHODS: This observational study included 1200 patients who underwent a kidney transplant between 1988 and 2003. The outcome was the occurrence of an ACS event within a maximum of 15 years after renal transplantation. RESULTS: Of all 215 deaths, 28.3% were caused by complications of CAD, the most common cause of death at our center. On multivariate analysis, diabetes (P = .005), prior transplant (P = .047), body mass index (BMI) at the time of transplant (P = .01), cholesterol level (P = .012), and low-density lipoprotein (LDL) level (P = .007) during 3 years after transplant were associated with early ACS. In conclusion, diabetes, prior transplant, BMI, cholesterol, and LDL were significantly associated with early ACS highlighting the importance of improved screening and perioperative management.

Comparison of spousal with other donor groups: Study of a single center.

In coping with the shortage of living-related and cadaveric donor groups for renal transplantation, and in the fear of organ marketing, spousal donors are considered an invaluable potential source. Survival rates have been reported to be as high as even some related groups. This study evaluated 1039 renal transplantations up to 2003. Patient survival rates in different donor groups were determined using the Kaplan-Meier method. The 3-year patient survival rates were 93% for kidneys from 61 spouses; 92% for kidneys from 433 living-related donors; 91% for kidneys from 427 living-unrelated (excluding spouses) donors; and 90.5% for 118 cadaveric kidneys. Such results were consistent with many other reports which consistently showed that spousal donors were at least as good as living-related donors, representing a reliable source in cases of organ shortage. The high survival rate of spousal donors is probably related to their strong emotional support.