International Journal of Radiation Research
Volume:19 Issue: 1, Jan 2020

Previous studies show inconsistent effect estimates for the efficacy of Endostar in patients with advanced non-small cell lung cancer (NSCLC) undergoing chemoradiotherapy. Therefore, this meta-analysis aimed to determine the effectiveness and safety on the basis of data obtained from available randomized controlled trials (RTCs). We find relevant articles reporting the use of Endostar combined with chemoradiotherapy regimens in the treatment of advanced NSCLC. The retrieval period was from June 2008 to June 2018. A total of 11 RTCs that recruited a total of 735 patients were included. Overall, the results indicated that patients who received Endostar plus chemoradiotherapy showed a significantly increased incidence of objective response rate (ORR) (relative risk [RR] = 1.48; 95% confidence interval [CI] = 1.31–1.67; P < 0.00001) and disease control rate (DCR) (RR = 1.17; 95% CI = 1.09–1.25; P < 0.00001) compared with those who received chemoradiotherapy alone. However, no significant difference was noted between groups for 1-year survival rate (RR = 1.06; 95% CI = 0.91–1.23; P = 0.48). Furthermore, combined Endostar with chemoradiotherapy did not yield a high incidence of stable and elevated Karnofsky performance score (RR = 1.06; 95% CI = 0.91–1.23; P = 0.48). Moreover, no significant difference was noted in the incidence of total toxicity between the two groups. The findings of our study indicated that treatment with Endostar plus chemoradiotherapy yielded a high incidence of ORR or DCR, but did not trigger excess adverse events in patients with NSCLC.

The design of intensity modulated radiation therapy (IMRT) plans is difficult and time-consuming. The retrieval of similar IMRT plans from the IMRT plan dataset can effectively improve the quality and efficiency of IMRT plans and automate the design of IMRT planning. However, the large IMRT plans datasets will bring inefficient retrieval result.

An intensity-modulated radiation therapy (IMRT) plan clustering method based on k-means algorithm and geometrical features is proposed to improve the retrieval efficiency from the IMRT plan dataset. The proposed method could benefit future automatic IMRT planning based on prior knowledge. In this study, a collection dataset including 100 cases of nasopharyngeal carcinoma IMRT plans was employed in the clustering experiment. The geometrical features of each cluster center were used to qualitatively predict the dosimetric characteristics of organs at risk (OARs) and compared with practical results.

Experimental results demonstrate that the tested dataset can be well clustered using the proposed method. The predicted dosimetric characteristics of OARs for each cluster agree well with their practical results, and the difficulty of IMRT planning for each cluster can be derived.

The proposed IMRT plan clustering method can bring great benefit to the new cases of IMRT planning.

The present study aimed to investigate the equivalent dose in vital organs, including heart and lung, due to secondary particles produced during breast proton therapy.

The numerical ORNL female-phantom was improved and simulated using the Monte Carlo MCNPX code. The depth-dose profile of proton beams with different energies was simulated. The proper energy range of incident proton beams has been estimated in order to have the Bragg peaks inside the breast tissue. The equivalent dose of secondary particles, including neutron and photon in vital organs, were evaluated. The TALYS code was used to investigate the neutron and photon particles’ production cross-sections.

The results showed that for the proton energy range of 60-70 MeV, the Bragg peaks positioned inside the breast. The maximum dose of 0.65 mSv/nA-p was in Heart-Left Ventricle due to neutrons production by incident 70 MeV protons. However, the maximum absorbed dose, due to the secondary particles, was less than 0.0004% of proton equivalent dose at the Bragg peak. The maximum photons dose and the protons dose into the Heart-Left Ventricle were 8.42 µSv/nA-p and 68.08 µSv/nA-p, respectively, which were negligible compared to the proton equivalent dose at the Bragg peak.

The results confirmed a noticeable lower dose in the heart and lungs for breast proton therapy, compared with the previously reported dose for breast radiotherapy using photon. Most of the dose absorbed by the organs is due to the secondary neutrons, but those are low enough to be neglected.

In head and neck radiotherapy, immobilization devices can affect dose delivery. In this study, a comprehensive end-to-end test was developed to evaluate the accuracy of radiotherapy treatment.

An Alderson Radiation Therapy (ART) anthropomorphic phantom with EBT3 film was used to mimic the actual patient treatment process. Ten patients treated for nasopharyngeal carcinomas with IMRT were retrospectively selected. For each patient, the treatment plan, as well as the targets and OARs was transplanted onto the phantom, and the IMRT plan was subsequently recalculated to the phantom with EBT3 film. Two quality assurance (QA) plans were generated, namely “Plan-with” wherein the immobilization device was contoured and “Plan-without” wherein it was omitted. EBT3 measurements were compared with the results of the TPS calculation.

With different gamma calculation criteria applied, the results obtained for Plan-with were closer to the dose measured with the EBT3 film. Moreover, 1.8% deviation was observed in the posterior neck skin dose for Plan-with when compared to the film measurements while the value was 33.1% lower for Plan-without. When compared to Plan-without, each target volume in Plan-with exhibited a 1–4% reduction in the maximum dose (D2%), minimum dose (D98%) and mean dose (Dmean).

Immobilization devices decrease the radiation dose to target volumes while increasing the skin dose and should be included within the body contour to ensure an accurate planning dose. The end-to-end IMRT test using an ART anthropomorphic phantom is a valuable tool to identify discrepancies between calculated and delivered radiation doses.

The publicchr('39')s understanding of radiation and protection of radiation harm is not high. Therefore, it is meaningful to know the radiation safety literacy level in terms of health care. This study developed a measurement tool that can help to identify the actual condition of radiation safety literacy and conducted the statistical assessment of the developed tool.

We developed a radiation safety literacy measurement tool in four steps: preliminary term extraction, content validity, face validity, and response scale composition using expert groups such as radiologist, professor of radiological science, angiography nurse, and professor of Korean language. And we developed a questionnaire and conducted a survey on samples of n = 280 (male: 124, female: 156). For statistical assessment, descriptive analysis, Cronbachchr('39')s coefficient, and correlation analysis were performed, and receiver operating characteristic (ROC) curve was obtained.

As a result of developing measurement tool of four steps, radiation safety literacy measurement tool consisting of a total of 46 items were developed. The result of the survey showed high reliability with the internal consistency reliability coefficient of 0.963. The correlation coefficient of the developed measurement tool with the rapid estimate of adult literacy in medicine was found to be valid with 0.448 (p<0.05).

The radiation safety literacy measurement tool developed in this study can be used as a useful tool for the process of patient evaluation for appropriate communication between the healthcare provider and the patient regarding radiation.

Naturally occurring radioactivity is a root cause of human exposure to harmful radiation. The occupational exposure hazard due to natural radionuclides occurring in drilling wastes is especially important in this regard. In this study the concentration of radionuclides namely 232Th, 226Ra and 40K were assessed in soil samples that were taken from various oil drilling areas.

10 samples were collected and sealed for two months to ensure the secular equilibrium between 226Ra and 232Th, and their respective radioactive progenies. The concentration of radionuclides in samples was measured by gamma spectroscopy. Descriptive and analytical statistics were used in order to analyze the data.

the results showed the average absorbed dose rates (D), annual effective dose (AED), Radium equivalent activity (Raeq) and various hazard indexes(Hex, Hin and Iγ ) for samples were 38.22 nGy/h, 0.046 mSv/y, 81.032 Bq/Kg, 0.21, 0.31 and 0.59, respectively.

The mean activity concentrations were lower than the world mean values, according to the radiation protection criteria that identified by UNSCEAR.

Polymer composites when reinforced with heavy metals in the form of micro/nano particles are efficient gamma- and X-ray shielding materials providing such advantageous features as cost-effectiveness, light-weight factor, flexibility, non-toxicity, conformability over conventional shields.

In this paper the influence of weight percentages and particle sizes of bismuth and tungsten contents of reinforced composites, i.e., bismuth/rubber (Bi/R) and tungsten/rubber (W/R) shields, in their photon absorption capabilities for photon energies, ranging from 40 to 350 keV, were investigated using both MCNPX simulations and measurements. The Bi/R and W/R polymer composites were prepared by mixing rubber with different weight percentages of bismuth and tungsten powders before exposing them to 152Eu gamma-rays. Then, the shielding efficiencies or photon transmission fractions, half-value layer (HVL) and tenth-value layer (TVL) of the samples were determined.

The simulation results confirmed that the particle size of the heavy element plays an important role in the shielding efficiency, especially at low photon energies. The decrease in the particle size of shielding material in each weight percentage improved the radiation shielding features. Therefore, the results supported the feasibility of nano-sized composite applications for shielding against low-energy photons, especially in diagnostic studies such as mammography.

At low photon energies, especially around 40 keV, a considerable decrease in photon flux was achieved by incorporating nano-sized heavy elements in a polymer matrix.

The present study intended to determine and report patient effective dose on the basis of patients and exposure data.

A nationwide computed tomography (CT) survey was provided as a report of patient doses in 2015-2016. Scan details were collected for nearly 2,000 adults and children in four age groups subjected to CT examinations. From total 565 CT scanners in different models in Iran, 120 different scanners were sampled. ImpactDose software was used to calculate the effective dose (ED) by collecting the necessary data also as an alternative fast method, the ED was estimated by multiplying dose length product (DLP) and a conversion factor.

There was a high variation in doses received by patients. The estimated EDs by the DLP and conversion factor were lower (except for sinus protocol) than those by ImpactDose software (p=0.014). The mean EDs were 1.09, 0.66, 7.70 and 13.29 mSv for adult patients’ procedures of head, sinus, chest and abdomen-pelvis, respectively. In terms of CTDIvol and DLP, in Iran the mean effective doses were significantly lower than other countries.

Publishing guidelines and exposure tables according to patient situations is necessary to decrease variations in doses and exposure parameters. Since the DLP conversion factor leads to a considerable discrepancy in calculating ED, when there is a need for precise dose calculations, the DLP conversion factor should not be used. Furthermore, it is suggested that ED be used as DRL, instead of CTDIvol.

Chest X-ray is one of the examinations required for an annual health checkup. The interaction of radiation to the medium produces free radicals, which consequently causes biological changes either structural or properties of the cells. Whether the radiation from Chest X-ray upright technique affects the plasma membrane fluidity of thalassemic red blood cells (RBCs) is still unclear.

Whole blood samples of non-thalassemia group (G1), non-clinically significant thalassemia group (G2) and clinically significant thalassemia group (G3) were irradiated with the Chest X-ray upright technique with a dose of 6.57 µSv (90 kVp). One-tube osmotic fragility (OF) test, dichlorophenol-indophenol (DCIP) test for hemoglobin E (HbE) screening and glucose-6-phosphate dehydrogenase (G6PD) activity analysis were performed on those samples.

The % OF values of G1 and G3, between irradiated and non-irradiated RBCs, were comparable, while those of G2 were significantly increased. However, the irradiation did not affect HbE screening test by DCIP technique in G2. In addition, it did not alter the G6PD activity in both thalassemia and non-thalassemia samples. 

Chest X-ray upright technique with a dose of 6.57 µSv (90 kVp) did not alter the membrane fluidity and the G6PD activity of thalassemic and non-thalassemic RBCs. Thus, it did not affect the thalassemia screening by OF and DCIP tests. However, increasing % OF value in HbE trait might be used as one of the screening test for HbE trait.

Excessive use of mobile phones is addictive and causes many complications. The severity of these complications depends on the duration of the call and the frequency of using mobile phones. Therefore, this study aimed to determine the effect of mobile phone waves on salivary secretion.

This descriptive study was conducted on 120 dental students in Rafsanjan, Iran, in 2015. Using the call history of the mobile phones, the number and duration of each personchr('39')s daily calls were obtained. The spitting method was used to collect unstimulated saliva, and stimulated saliva was collected with the help of natural chewing gums without sugar and additive flavors. After sampling, the falcon tubes containing saliva were centrifuged at 2500 rpm for 10 minutes. Then the saliva volume was read from the tube and recorded. Independent two-sample t test, one-way ANOVA, and multiple linear regression model were used for data analysis.

Students who talked for more than 40 minutes or 20-40 minutes a day on their mobile phones had a mean unstimulated salivary secretion of 0.885 and 0.331 ml/min, respectively and mean stimulated salivary secretion of 0.702 and 0.708 ml/min, respectively more than students who talked less than 20 minutes a day on their cell phones (P<0.05).

The results showed that increased duration of cell phone calls was associated with increasing the amount of stimulated and unstimulated salivary secretion, which could decrease the risk of developing oral infections and tooth decay.

Radionuclides occur in coal combustion residues, such as fly ash and bottom ash, which are by-products of coal combustion. They pose potential radiological risks to people present in the surrounding areas.

Gamma spectrometry was performed to determine the radionuclide activity concentrations in a coal-driven power plant located in the Limpopo province, South Africa, to assess the radiological impacts of the ash stored in ash dumps adjacent to the plant.

The mean (+ SD) activity concentrations were found to be 144.3±4, 62±2.1, and 315.9±4.9 Bq/kg for 226Ra, 232Th, and 40K, respectively, which are comparable to those found in previous studies. The radium equivalent activity was determined to be 258.43 Bq/kg. The average values of internal and external hazard indices were 1.09 and 0.70, respectively. With the exception of the internal hazard index, all the other indices were within the prescribed ranges indicated by the literature. Furthermore, the mean total annual effective dose received by plant workers was found to be 0.070 mSv/y, which is within the limit of 1.0 mSv/y prescribed by the IAEA. The average excess lifetime cancer risk value was 0.49 × 10-3, which is higher than the UNSCEAR precautionary limit of 0.29 × 10-3 but lower than the ICRP limit of 0.05 for low-level radiation.

Ash dust inhalation was identified as the most significant exposure pathway among plant workers. However, the results demonstrated that storing of ash at this plant does not constitute any radiological threat to people in the adjacent regions.

It remains unclear whether radiation-induced haemorrhage in the spleen causes iron accumulation, and subsequently, ferroptosis in splenic lymphocytes. In this study, we investigated the occurrence of ferroptosis in splenic lymphocytes of gamma-irradiated mice.

Mice were subjected to gamma radiation from a 137Cs source. Iron, Ferroportin 1, and iron regulatory protein (IRP) levels in the spleen, and serum iron and hepcidin levels in the blood were measured to study the change in iron metabolism of the irradiated spleen. After Ferrostatin 1/LDN193189 was intraperitoneally injected into mice post-irradiation, the viability of splenic lymphocytes and the splenic index were evaluated to investigate the mechanism of damage induction in splenic lymphocytes. The survival rate of mice was evaluated to identify the radiation mitigator based on the inhibition of ferroptosis.

Iron accumulation (up to 0.62 g/g) observed in the spleen of irradiated mice was due to haemorrhage-based haemosiderin. The iron accumulation triggered the IRP-ferroportin 1 axis to increase the level of serum iron to 121.65 mmol/l. LDN193189 was used to demonstrate that the iron accumulation decreased the viability of splenic lymphocytes in irradiated mice, which was subsequently demonstrated to attribute to ferroptosis with the use of Ferrostatin 1 and through detection of ferroptosis-related parameters. The survival rate of irradiated mice was improved upon Ferrostatin-1 (60% with a duration of 120 days) or LDN193189 (40% for the same duration) treatment.

Radiation-induced haemorrhage causes ferroptosis in splenic lymphocytes, and anti-ferroptosis is a potential strategy to alleviate immune damage in hematopoietic acute radiation sickness.

This work investigated radioactive contamination in soils of the pine forest in the territory adjacent to Semipalatinsk test site.

Thirty samples from the soil were collected from six different a soil profile was laid out (research areas). Activity concentrations of 137Cs and 241Am were determined using a Canberra GX-2020 solid-state gamma-spectrometer system. Activity concentrations of 90Sr and 239+240Pu were determined after application of radiochemical analysis. In addition, the soil physicochemical characteristics such as pH value, the amount of organic content and texture of soil were investigated by pH meter, the Tiurin’s techniques, modified by Nikitin, and particle size distribution (Pipette) methods, respectively.

The highest specific activity values were registered for 241Am (up to 64 Bq/kg) and 239+240Pu (up to 75 Bq/kg) transuranium radionuclides. Maximum concentrations of 241Am, 137Cs and 239+240Pu were registered in the top 5-cm layer, while 90Sr is uniformly distributed up to the depth of 20 cm. In general, researched artificial radionuclides by their level of mobility in vertical soil profile can be arranged in sequence as follows: 90Sr > 239+240Pu > 241Am > 137Cs.

137Cs by the character of its distribution in vertical soil profile is similar to its vertical distribution in brown soils at conditionally «background» STS territories. Mobility of 241Am, 239+240Pu and 90Sr in brown soils at the researched territory is higher than at conditionally «background» territories of the STS.

The aim of this study was to investigate the effect of the electromagnetic field (EMF) generated by 10 kV (50 Hz) high voltage line on the epididymal sperm characteristics and the protective effects of ganoderma lucidum (GL) and melatonin (M) in EMF exposed male rats.

In this study, 64 Wistar rats were divided into 8 groups (n= 8). Rats in 26-day and 52-day experiment groups were exposed to EMF for 8 hours daily during 26 and 52 days respectively. Rats in EMF+GL-26 and EMF+GL-52 groups were treated with GL by oral gavage 20 mg/kg daily and rats in EMF+M-26 and EMF+M-52 groups received M 10 mg/kg daily during experiments. At the end of experiments, all rats were sacrificed and epididymal sperm concentration, motility and morphology were evaluated.

In the 26-day experiment, sperm motility of the control group were significantly lower than all groups (P<0.05). In the 52-day experiment, the EMF+GL52 group had the lowest tail and total morphologic defect rates and the differences between this group and EMF52 and EMF+M52 groups were significant.

Our data demonstrated that; (1) EMF exposure can have different effects on sperm quality according to duration of exposure, (2) treatment of GL in rats exposed to EMF for 26 or 52 days increased sperm concentration and reversed negative effect of EMF on sperm morphology, respectively and (3) treatment of M in rats exposed to EMF for 26 or 52 days had negative effects on sperm concentration and sperm morphology, respectively.

Salivary glands (SGs) are usually irradiated during radiotherapy for head and neck cancers, which may lead to radiation-induced changes. These changes could be evaluated safely by ultrasonography; however, there have been few studies in this regard. Thus, we aimed to investigate the changes in post-radiotherapy submandibular glands using ultrasonography in patients undergoing head-neck radiotherapy.

We evaluated 46 submandibular glands of 23 patients ultrasonographically in terms of echogenicity, echotexture, margin, and dimensional (anteroposterior, superoinferior, mediolateral length and volume) changes before radiotherapy, and at the second and sixth months after radiotherapy.

About 93.5% of the submandibular glands were hyperechoic before RT. When the same submandibular glands were evaluated two months later, 39.1% were hyperechoic. Six months after the therapy, 56,5% were hyperechoic (p<0.001). There is also a similar trend for the echotexture (p<0.001) and the regularity margins before RT, two months after-, and at sixth month after RT (p<0.001). Also, there were statistically significant differences between anteroposterior, superoinferior, mediolateral lengths, and volumetric values measured before radiotherapy and at the end of two and six months after radiotherapy onset (p<0.001).

We revealed that submandibular glands were isoechoic or hypoechoic, heterogeneous, and irregular after radiotherapy; however, as the time elapsed after radiotherapy, the parenchyma structure returned to normal in half of them. Indeed, defining radiotherapy-related changes in SGs may be helpful in better understanding the mechanism of common oral complications associated with RT, and in the differential diagnosis of other SG diseases.

Mobile phones as an electronic device which are emitting radiofrequency-electromagnetic field (RF-EMF). In this study was intend to determine the contingent effects of cell phone induced RF-EMF on testicular tissue in adolescence.

Rats in the RF-EMF group were exposed to 900 MHz RF-EMF, while sham and control rats were not. After the completion of the test steps, the testicular tissues which were rapidly removed from the body of sacrificed rats were examined by using histopathological and biochemical methods. Testicular tissues cut to 5 µm thickness undergo routine histological procedures. Thus, histopathological evaluation will be completed. Malondialdehyde (MDA), glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) levels in testicular tissues were measured by biochemical methods to determine whether oxidative stress occurred or not.

Histopathologic findings were not observed in any of the studied groups. There was also no difference between the groups in terms of localization of androgen and estrogen receptors. The incidence of apoptotic index and TUNEL-positive cells was similar in all three groups. In the RF-EMF group, although the levels of MDA and CAT were significantly higher, GSH levels were lower than the other groups. There was no essential difference between the groups in terms of SOD level.

The obtained results of this study showed that exposed to 900 MHz RF-EMF in adolescents caused oxidative stress in the testes, but testicular damage which is caused to oxidative stress is remained too low to be detected by histopathological methods in this study.

The herb feverfew (Tanacetum parthenium L., Asteraceae) has an ancient reputation as an effective anti-inflammatory, analgesic, antipyretic, and anti-asthmatic agent. Parthenolide a gemacranolide-type sesquiterpene lactone is the major constituent of European feverfew.

The present study was intended to evaluate the in vivo antioxidant potential and radioprotective ability of  Tanacetum parthenium leaf extract and synthetic Parthenolide. Male mice were orally administered with Tanacetum parthenium leaf extract and synthetic Parthenolide for 15 days followed by electron beam irradiation exposure. Survival studies in mice exposed to a lethal dose of 10Gy. At 6.0 Gy radioprotective ability was performed in order to find the nature of the compound.

The mice liver supernatant was used to measure total antioxidant capacity(TAC), glutathione (GSH) content along with various antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT) after electron irradiation exposure at 6.0 Gy. Pretreatment with Tanacetum parthenium extract and synthetic Parthenolide, prior to electron beam irradiation resulted in the increased survival rate of the animals as compared to the irradiated group. The treatment groups followed by electron beam irradiation at 6 Gy were significantly higher than the controlled group and the irradiated group, showing immunomodulatory nature. Pre-treatment and post-treatment with Tanacetum parthenium extract and synthetic Parthenolide, also significantly enhanced the activity of antioxidant enzymes and improved hematological parameters.

The present study suggests that supplementation with leaf extract of Tanacetum parthenium and synthetic compound parthenolide has potent antioxidant activity and act as a probable radioprotector against electron beam radiation-induced oxidative damage.

To retrospectively evaluate whether quantitative information derived from spectral imaging can improve the differential diagnosis of pancreatic cystic masses including pancreatic solid pseudopapillary epithelial neoplasms (SPENs), mucin- producing cysts and pseudocysts.

From June 2015 to October 2017, 56 patients (22 pseudocysts, 18 mucin-producing cysts and 16 SPENs) who underwent spectral CT imaging were included in the study. Conventional characteristics and quantitative parameters were compared among the three groups. The receiver-operating characteristic curve was used to evaluate the diagnostic performance of parameters which had statistical significance among the three groups. Two radiologists diagnosed the pancreatic cystic masses blinded in consensus, without and with the information of the statistical analysis.

The conventional characteristics including age, contour, nodule and septum were the independent factors correlated with category. The quantitative parameters including effective-Z, slope of energy spectral curve (slope), iodine (water) concentration and calcium (water) concentration demonstrated significantly lower values in pseudocysts group when compared with mucin-producing cysts and SPENs groups. Slope in portal venous phase, threshold of less than 0.50, was the best discriminator between pseudocysts group and mucin-producing cysts group, with a sensitivity of 95.5%, and a specificity of 88.9%. The best quantitative parameter for differentiate SPENs from mucin-producing cysts was the iodine (water) concentration in portal venous phase. With the knowledge of statistical analysis, the accuracy of the two radiologists increased from 78.5% to 90.9%.

Multi-parametric analysis with the combination of quantitative parameters derived from CT spectral imaging could improve the diagnostic performance.

Intensity Modulated Radiotherapy (IMRT) can improve radiotherapy (RT) results by improving healthy tissue sparing. Additionally, IMRT provides more consistent dose deliveries and suppresses secondary tumor formation. RT is a principal treatment in breast cancer (BC).

To evaluate the outcome of the Radiotherapy Plans (RTP) that use IMRT technique to left breast and other organs, including left lung (Lt lung), right lung (Rt lung), heart, and spinal cord.

Thirteen patients with left-sided breast carcinoma were treated using IMRT.

The Homogeneity Index (HI) and Conformity Index (CI) showed significant improvement over IMRT-involved plans. All IMRT plans significantly improved CI for 12 patients, where CI <1. Planning target volume (PTV) was under coverage, except for patient No. 6, where CI>1. HI for 13 patients.  Mean dose to heart, Lt lung, and Rt lung was (9.966±1.261), (14.388±0.854), and (4.083±0.661) of the prescribed dose, respectively. Cord Max, Dose was (Gy) (20.751±7.384), and Cord Received Max Dose was <45Gy.  Mean heart dose was (9.966±1.261) (Gy), and the PTV mean dose was (41.169±0.437) (Gy). Mean dose to lungs for eight patients was <30Gy, except for five patients (No. 1, 2, 5, 12, and 13), which received >30Gy.

The IMRT plans achieved a significant reduction in heart volume and ipsilateral lung exposed to high-dose (≥40.05 Gy).  Multi-beam inverse planned IMRT technique might benefit patients with heart diseases, and who are exposed to doses <20 Gy, irrespective of the selected plan.  Relative volume of ipsilateral lung or heart receiving high-dose (40.05 Gy) was significantly reduced.

During radiation therapy, stromal cells surrounding the tumor (e.g mesenchymal stem cells) may affect the treatment outcomes. We aimed to investigate the effects of gamma radiation on the mRNA expression of cytokines, DNA damage and population doubling time (PDT) of adipose-derived mesenchymal stem cells (ASCs).

ASCs were enzymatically extracted from breast tissue and exposed to different doses of 5, 10, and 30 Gy of gamma radiation. The capability of ASC proliferation, the level of DNA damage, and the expression of angiogenic and immunosuppressive factors were evaluated using PDT, comet assay, and qRT-PCR, respectively.

Gamma irradiation of ASCs with different doses of 5, 10, and 30 Gy significantly increased PDT and DNA damage in a dose-dependent manner (P< 0.05). A dose of 5 Gy caused a significant increase in SDF-1 whereas a 10 Gy dose significantly increased the expression of both SDF-1 and IL-10 (P< 0.05) in ASCs.

Results indicate that different doses of gamma irradiation may induce angiogenesis and immunosuppression in ASCs via different cytokines which may affect the radiotherapy outcome.

The induction of bystander effect via ionizing radiation has been well proven. However, few studies have investigated the bystander effect following non-ionizing radiation, such as ultrasound waves. Here, the bystander effect after different sonication times on human melanoma cell line (A375), is evaluated by assessing cell viability and apoptosis.

The cells were divided into two main target and bystander groups. Target cells were exposed to 1 MHz ultrasound at 2 W/cm² intensity for 1, 2, 5 and 10 min with an ultrasound unit. Then, bystander cells received the cell culture medium of target cells. MTT and flow cytometry assays were used to determine the cell’ viability at different times after exposure and medium transfer, as well as the detection of apoptosis.

The cell’ viability in ultrasound-exposed target cells was less than 75% for 24 and 48 h incubation. Furthermore, bystander cell’ viability was not significantly different from the control group 1 and 12 h after receiving the culture medium of target cells. However, bystander cells viability 24 and 48 h after target cells medium transfer was significantly decreased (P=0.01). The apoptosis rate of bystander cells, 24 and 48 h after receiving the cell culture medium of target cells, showed significant differences from the control group.

This research results revealed that the ultrasound waves could induce a biological effect in A375 bystander cells which were not directly exposed to direct ultrasound.

This study investigated the γ-rays shielding properties of some building materials in Sudan has been investigated.

Photons attenuation coefficients and half value layer (HVL) were experimented using Cs-137 and Co-60 sources.  The measurements were performed to gauge the intensity of radiation when performed unshielded, the specific thickness of selected samples was examined, using an ion chamber placed at 2 meters from Cs-137 and Co-60.

The results indicated that the linear attenuation coefficient (µ) possesses a linear relationship with the corresponding densities of the samples studied and inversely with photon energy. HVL was directly proportional with photon energy.

As a result of this evaluation the study concluded that selected samples were suitable as shielding material for gamma radiation in Sudanese laboratories.

Salivary flow rate (SFR), to estimate salivary gland dysfunction and radioactivity in different body fluids, to evaluate its intensity, were determined in thyroid patients after 131-I therapy.

For determination of SFR an innovative sponge test was adopted and the radioactivity in saliva, blood and serum of thyroid patients was determined by NaI (TI) Scintillation Radiation Detector.

There was a significant reduction in SFR at 2 weeks after RAIT. At 3 hours after administration of 555−1073 MBq to the benign thyroid patients, the radioactivity in 1 g of saliva, 2.5 mL of blood and 0.6 mL of serum was 17.24, 0.74 and 0.25 MBq respectively. In the same patients, at 2 weeks after RAIT, the radioactivity was decreased and was found to be 0.22, 0.13 and 0.09 MBq in saliva, blood and serum respectively. In malignant thyroid patients treated with 3700−9250 MBq, the radioactivity at 3 hours after RAIT in the studied samples of saliva, blood and serum was 200.72, 9.14 and 3.07 MBq and at 2 weeks after RAIT, radioactivity in samples was decreased up to 0.15, 0.05 and 0.03 MBq respectively.

An indigenously designed sponge test was simple, safe and quick method to determine the SFR. The sudden increase of radioactivity was found in all studied samples within 3 hours after RAIT and reduced significantly at 2 weeks after RAIT. The raised radioactivity at 3 hours after RAIT was sufficient to impart its harmful effects even to all interactive persons.

Although ionizing radiation is a risk factor, it is a therapeutic agent for cancer.

The protective and defensive effect of L-Carnitine and vitamin E on gastrointestinal tract organs (liver, spleen and intestine) post whole body gamma irradiation exposure.

56 male albino rats, which were divided into four groups (14 rats per group); group (I): Control group, group (II): rats were irradiated with a single dose of whole body gamma rays (6 Gy) and left 4 weeks. Group (III): rats were given L- Carnitine for five days, then irradiated by same dose. Group (IV): rats were received L- Carnitine and vitamin E for five days then irradiated by same dose. At 1 and 4 weeks post radiation exposure, seven rats from each group were scarified, blood and GIT tissue samples were collected.

Liver and blood samples: radiation related degenerative damage was obviously higher in the radiation group than the control group with elevated liver enzymes, however pretreatment groups revealed reduced radiation induced acute liver damage compared to the radiation group with significant improvement in liver enzymes. Spleen and intestinal samples: radiation induced damage were significantly higher in the radiation group versus the control group, however, in pre-treatment groups no significant improvement in radiation induced effects were noted compared with radiation group.

A great radio protective effect of both L- carnitine and vitamin E after radiation exposure mainly in liver tissue and its enzymes but not in both spleen and intestinal tissue.

Reliable estimation of radiation-absorbed dose is necessary to evaluate the benefits and the risks of radiopharmaceuticals used for diagnostic or therapeutic purposes in nuclear medicine. Materiel and

This study included 47 patients treated with iodine-131 for Graves’ disease. A comparative study between Geant4 Monte Carlo simulation and MIRD formalism was carried out to evaluate the dose received by each patient. Patients’ thyroids and internal radiation were modeled using Geant4. Geant4 simulations were compared to experimental measurements performed with TLDs placed inside an ellipsoidal Thyroid phantom. MIRD was used to determine the beta doses received by the different patients.

The average difference between MIRD and Geant4 considering only beta emitted radiation was approximately 5.6%; this difference is justified by the fact that, Geant4, contrary to MIRD, considers all particle energies of the 131I spectrum, the shape of the thyroid and the heterogeneity of the dose deposited in the modeled volume. A good agreement was found between experiment and Geant4 simulations. The total dose received by patients varies between 176Gy and 359Gy. After 9 month, 74% of treated patients were rendered hypothyroid.

This study showed the necessity of determining the specific activity of each patient considering the thyroid volume and the iodine fixation. It also revealed that the Geant4 toolis appropriate for accurate internal dosimetry calculations, particularly for the case of Graves’ disease treatment. GEANT4 can be used as a standard for the comparison of experimental measurements.

Worldwide the computed tomography (CT) scanning is recognized as a high radiation dose modality. This article aimed to estimate the radiation dose reduction and radiogenic risks for adult patients undertaking abdominal CT examinations.

A total of 128 patients were studied using 2, 4, 16 and 64 slice CT scanners. The patients were divided into two categories: the first category as control category (80 patients), and the other as optimisation category (48 patients). The optimisation protocol was based on decreasing the gantry rotation time.

In general, the faster gantry rotation times (0.7 s/rot and 0.5 s/rot) resulted in dose reduction while maintaining images noise within the acceptable range. After dose optimization, the overall cancer risk was reduced by 21%, 49%, 29%, and 16%, for the patients undergoing abdominal examinations on 2, 4, 16 and 64 slice CT scanners, respectively.

The patient dose optimisation during CT abdomen was investigated. By lowering gantry rotation time, a radiation dose reduction of up to 30 % was achieved without compromising the diagnostic findings. Accordingly, the attention of all technologists necessary to take advantage of the dose reduction methods reported in this study.

In intensity modulated radiation therapy, cone beam computed tomography (CT) has been used to evaluate patients prior to treatment. This study conducted a comparative evaluation of the image reconstruction ability of the clinically used half-fan bowtie filter and the full-fan bowtie filter. Materals and

A CT simulation marker was inserted inside a human phantom, and the pelvic region, a large field-of-view region, was scanned by moving the isocenter along the x-axis ±1–5 cm with the full-fan mode. Furthermore, image verification was conducted based on the planning CT image and bone to confirm the setup correction value. The obtained value was then compared with that from the clinically used half-fan scan.

The evaluation of the reconstructed image (from the isocenter to the marker) after setting the median line did not show a significant difference with respect to the image obtained using the half-fan scan. Planning CT images and setup errors were compared in three directions, and the results showed that each mean value was within the margin of error (±3 mm). The 3D vector value was determined to be within 0–2.45 mm, and the comparison of the value obtained from the half-fan scan showed no statistically significant result.

The application of a phantom study to actual patients in the future will reduce the error caused by movement during the treatment due to the short scan time and will reduce the imaging dose for patients during setup error confirmation and correction.

In the present study, a case was reported concerning a patient with a bulky extremity soft tissue sarcoma treated with spatially fractionated Grid therapy and then followed by standard external beam radiotherapy. Treatment was performed using a Grid block to deliver 15 Gy in one fraction. There was one week interval break before EBRT treatment with 50 Gy in 25 fractions for the neoadjuvant external beam radiotherapy. The surgery was performed 4 weeks after the completion of radiotherapy. The follow-up time was considered as 24 months. The patientchr('39')s general condition was good during this period without the presence of tumor recurrence or grade 3 or 4 treatment-related toxicities. Combining different treatment techniques like grid therapy is feasible and may  improve the outcomes in the management of bulky high-grade soft-tissue sarcomas of the extremities.