H. Gao, Y. Wan, X. Bu, X. Fan, X. Xie, X. Ji, W. Song
Hypoxia, a common phenomenon in solid tumors can promote dysfunctional vascular growth and epithelial-to-mesenchymal transition, leading to cell mobility and metastasis. The decreased sensitivity of hypoxic tumor cells to ionizing radiation is one of the main factors affecting the effect of conventional radiotherapy. It is well known that conventional radiotherapy mainly reduces the effect of hypoxic radiation resistance by reoxygenation between fractions. With the improvement of radiation treatment planning and delivery, more and more cancer patients have been treated with hypofractionated radiotherapy (HFRT), which have achieved a much higher effect than conventional radiotherapy. Given that HFRT is delivered within one or a few fractions, does tumor hypoxia affect its efficacy? Is there any way to further improve the effect of HFRT? In this review, we focus on the interaction between HFRT and hypoxia, and how to optimize the regimen of HFRT to decrease the effect of hypoxia and improve the efficacy is discussed in detail.
{"title":"How to deal with the relationship between hypoxia and radiotherapy in the hypofractionated radiotherapy era","authors":"H. Gao, Y. Wan, X. Bu, X. Fan, X. Xie, X. Ji, W. Song","doi":"10.29242/IJRR.19.4.759","DOIUrl":"https://doi.org/10.29242/IJRR.19.4.759","url":null,"abstract":"Hypoxia, a common phenomenon in solid tumors can promote dysfunctional vascular growth and epithelial-to-mesenchymal transition, leading to cell mobility and metastasis. The decreased sensitivity of hypoxic tumor cells to ionizing radiation is one of the main factors affecting the effect of conventional radiotherapy. It is well known that conventional radiotherapy mainly reduces the effect of hypoxic radiation resistance by reoxygenation between fractions. With the improvement of radiation treatment planning and delivery, more and more cancer patients have been treated with hypofractionated radiotherapy (HFRT), which have achieved a much higher effect than conventional radiotherapy. Given that HFRT is delivered within one or a few fractions, does tumor hypoxia affect its efficacy? Is there any way to further improve the effect of HFRT? In this review, we focus on the interaction between HFRT and hypoxia, and how to optimize the regimen of HFRT to decrease the effect of hypoxia and improve the efficacy is discussed in detail.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48243190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhen-chao Tao, J. Qiu, Yangyang Zhang, L. Qian, Jing Gao, Yan Zhou, Liping Yang, Jian He, Jing Yang, Rui Wang, Yifan Huang, Lingran Zhou, Bin Sun, Y. Cui
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.
{"title":"Chemoradiotherapy alone or in combination with Endostar for patients with advanced non-small cell lung cancer: A systematic review and meta-analysis","authors":"Zhen-chao Tao, J. Qiu, Yangyang Zhang, L. Qian, Jing Gao, Yan Zhou, Liping Yang, Jian He, Jing Yang, Rui Wang, Yifan Huang, Lingran Zhou, Bin Sun, Y. Cui","doi":"10.29252/IJRR.19.1.1","DOIUrl":"https://doi.org/10.29252/IJRR.19.1.1","url":null,"abstract":"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.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41680782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Asgari, H. Afarideh, H. Ghafoorifard, E. A. Amirabadi
Background: Polymer composites when reinforced with heavy metals in the form of micro/nano particles are efficient gammaand X-ray shielding materials providing such advantageous features as cost-effectiveness, lightweight factor, flexibility, non-toxicity, conformability over conventional shields. Materials and Methods: 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 Eu gamma-rays. Then, the shielding efficiencies or photon transmission fractions, half-value layer (HVL) and tenthvalue layer (TVL) of the samples were determined. Results: 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. Conclusions: 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.
{"title":"Effects of particle size and weight percentage of heavy metal elements on photon shielding efficiency of reinforced polymer composites","authors":"M. Asgari, H. Afarideh, H. Ghafoorifard, E. A. Amirabadi","doi":"10.29252/IJRR.19.1.55","DOIUrl":"https://doi.org/10.29252/IJRR.19.1.55","url":null,"abstract":"Background: Polymer composites when reinforced with heavy metals in the form of micro/nano particles are efficient gammaand X-ray shielding materials providing such advantageous features as cost-effectiveness, lightweight factor, flexibility, non-toxicity, conformability over conventional shields. Materials and Methods: 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 Eu gamma-rays. Then, the shielding efficiencies or photon transmission fractions, half-value layer (HVL) and tenthvalue layer (TVL) of the samples were determined. Results: 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. Conclusions: 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.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46673054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement of exposure to radionuclides (40-K, 226-Ra, and 232-Th) in the oil and gas drilling industry","authors":"J. Deris, B. Dehaghi","doi":"10.29252/IJRR.19.1.49","DOIUrl":"https://doi.org/10.29252/IJRR.19.1.49","url":null,"abstract":"","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42542525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: Purpose of the study is to evaluate field-in-field (FIF) and slidingwindow intensity modulated radiation therapy (SW-IMRT) treatment plans in terms of homogeneity index (HI), conformity index (CI) and normal tissue doses for organs at risk (OAR) in patients with endometrial carcinoma along with deriving a new expression for CI. Materials and Methods: Four different FIF plans with different MLC (multi-leaf collimator) margins and SW-IMRT plan were compared in 20 endometrial cancer patients who underwent adjuvant pelvic radiotherapy with 50.4 Gy in 28 fractions. Normal tissue doses were assessed for OAR from dose volume histograms (DVHs). HI and CI values were calculated according to the reports of International Commission on Radiation Units and Measurements (ICRU)-83, Radiation Therapy Oncology Group (RTOG) 1993 and ICRU-62. A new CI was developed and named CIOPT standing for optimized conformity index. Results: SW-IMRT provided a significantly better CI in comparison to other FIF plans (p< 0.001). Conventional-FIF (C-FIF) was the most homogeneous plan compared to all other FIF plans and SW-IMRT (p≤0.001). The absolute volume of small intestine that received ≥45 Gy (V45) and doses received by a 30% volume of rectum (D30) were dramatically reduced in SW-IMRT (p < 0.001). Conclusion: MLC margins had a substantial influence on OAR doses, HI and CI. A close proximity of CIOPT to 1 indicated that this formulation of CI was a useful plan evaluation tool, which was also compatible with the RTOG 1993 and ICRU-62
{"title":"Dosimetric evaluation of field-in-field and sliding-window IMRT in endometrium cancer patients with a new approach for the conformity index","authors":"Alper Ozseven, E. Ozkan","doi":"10.52547/IJRR.18.4.853","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.853","url":null,"abstract":"Background: Purpose of the study is to evaluate field-in-field (FIF) and slidingwindow intensity modulated radiation therapy (SW-IMRT) treatment plans in terms of homogeneity index (HI), conformity index (CI) and normal tissue doses for organs at risk (OAR) in patients with endometrial carcinoma along with deriving a new expression for CI. Materials and Methods: Four different FIF plans with different MLC (multi-leaf collimator) margins and SW-IMRT plan were compared in 20 endometrial cancer patients who underwent adjuvant pelvic radiotherapy with 50.4 Gy in 28 fractions. Normal tissue doses were assessed for OAR from dose volume histograms (DVHs). HI and CI values were calculated according to the reports of International Commission on Radiation Units and Measurements (ICRU)-83, Radiation Therapy Oncology Group (RTOG) 1993 and ICRU-62. A new CI was developed and named CIOPT standing for optimized conformity index. Results: SW-IMRT provided a significantly better CI in comparison to other FIF plans (p< 0.001). Conventional-FIF (C-FIF) was the most homogeneous plan compared to all other FIF plans and SW-IMRT (p≤0.001). The absolute volume of small intestine that received ≥45 Gy (V45) and doses received by a 30% volume of rectum (D30) were dramatically reduced in SW-IMRT (p < 0.001). Conclusion: MLC margins had a substantial influence on OAR doses, HI and CI. A close proximity of CIOPT to 1 indicated that this formulation of CI was a useful plan evaluation tool, which was also compatible with the RTOG 1993 and ICRU-62","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42097273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: One of the main sources of exposure to radiation is terrestrial radionuclides in the environment. These radioisotopes are present in the Earth's crust and can be increased by human activity such as mining of coal, oil, and minerals. Materials and Methods: In this study, 39 soil samples including virgin and cultivated were collected from around of the Shazand Refinery Complex(SRC) using a template and experimental method. The gamma spectrometry method was used to measure the specific activity of the Ra, Th, K and Cs radionuclides. Results: The average concentrations of Ra, Th, K and Cs in the cultivated (virgin) soil samples were 21.95 ± 0.27 (23.99 ± 0.37), 25.37 ± 0.29 (31.74 ± 0. 38), 416.72 ± 1.88 (461.09 ± 2.68) and 5.13 ± 0.08 (5.51 ± 0.14) in Bq kg. Excess lifetime cancer risk (ELCR) was obtained for cultivated (virgin) soil as 0.19 × 10 (0.22 × 10), which is close to the world average (0.29 × 10) and lowers than the maximum acceptable value (10). Conclusion: The specific activities of natural radionuclides were in the global range and are lower than the maximum allowable value. The distribution map of Ra and Cs indicated some part of Ra, distributed as fly ash from a chimney, caused by the incineration of refinery waste. The radiological parameters calculated for both types of soil were lower than the maximum admissible values, and therefore there is no radiological hazard for people living in this area.
{"title":"Radiometric properties of virgin and cultivated soil around the Shazand Refinery Complex in Iran","authors":"M. Mohebian, R. Pourimani","doi":"10.52547/IJRR.18.4.723","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.723","url":null,"abstract":"Background: One of the main sources of exposure to radiation is terrestrial radionuclides in the environment. These radioisotopes are present in the Earth's crust and can be increased by human activity such as mining of coal, oil, and minerals. Materials and Methods: In this study, 39 soil samples including virgin and cultivated were collected from around of the Shazand Refinery Complex(SRC) using a template and experimental method. The gamma spectrometry method was used to measure the specific activity of the Ra, Th, K and Cs radionuclides. Results: The average concentrations of Ra, Th, K and Cs in the cultivated (virgin) soil samples were 21.95 ± 0.27 (23.99 ± 0.37), 25.37 ± 0.29 (31.74 ± 0. 38), 416.72 ± 1.88 (461.09 ± 2.68) and 5.13 ± 0.08 (5.51 ± 0.14) in Bq kg. Excess lifetime cancer risk (ELCR) was obtained for cultivated (virgin) soil as 0.19 × 10 (0.22 × 10), which is close to the world average (0.29 × 10) and lowers than the maximum acceptable value (10). Conclusion: The specific activities of natural radionuclides were in the global range and are lower than the maximum allowable value. The distribution map of Ra and Cs indicated some part of Ra, distributed as fly ash from a chimney, caused by the incineration of refinery waste. The radiological parameters calculated for both types of soil were lower than the maximum admissible values, and therefore there is no radiological hazard for people living in this area.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45449165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Hosseini, A. Banaei, Z. H. Motlagh, R. Abedi-Firouzjah, F. Falahati, H. Zamani, Y. Moghimi
Background: The aim of this study was to estimate the cancer risks and mortalities of different types induced by routine examinations of digital radiography for one year in Mazandaran province, Iran. Materials and Methods: Radiation parameters and calculated entrance skin dose (ESD) values of 13 digital radiographic examinations were collected from 2340 patients at 18 high-patient-load radiography centers. Organ mean doses were estimated based on the collected parameters applying PCXMC software. The BEIR VII-Phase 2 model was used to calculate the induced cancer risks and mortalities of various cancer types at different ages. Results: The average ± standard deviation (SD) lifetime risks (incidence probability in 100,000 people) induced by radiations from radiography examinations for one year was 51.29±4.73 and 99.62±7.36 for new-born males and females, respectively. The lifetime cancer risk decreased with age and reached 3.77±0.62 and 4.88±0.07 for 80-year men and women, respectively. The average lifetime risks of mortality due to cancers induced by annual radiographies were obtained at 14.18±1.62 and 22.83±2.55 for new-born males and females, respectively. This risk reduced with age and was reached 1.97±0.27 and 2.45±0.38 for men and women at the age of 80 years, respectively. Conclusion: Our results showed that there are low but significant risks of cancer incidence for patients undergoing digital radiography, which included a large percentage of the population in Mazandaran province, especially for children and newborns. Therefore, further efforts like appropriate patient setup and beam geometry should be carried out to decrease patient doses.
{"title":"Estimating the cancer risk and mortalities induced by routine digital radiography examinations on patient of different ages in Mazandaran province","authors":"S. Hosseini, A. Banaei, Z. H. Motlagh, R. Abedi-Firouzjah, F. Falahati, H. Zamani, Y. Moghimi","doi":"10.52547/IJRR.18.4.875","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.875","url":null,"abstract":"Background: The aim of this study was to estimate the cancer risks and mortalities of different types induced by routine examinations of digital radiography for one year in Mazandaran province, Iran. Materials and Methods: Radiation parameters and calculated entrance skin dose (ESD) values of 13 digital radiographic examinations were collected from 2340 patients at 18 high-patient-load radiography centers. Organ mean doses were estimated based on the collected parameters applying PCXMC software. The BEIR VII-Phase 2 model was used to calculate the induced cancer risks and mortalities of various cancer types at different ages. Results: The average ± standard deviation (SD) lifetime risks (incidence probability in 100,000 people) induced by radiations from radiography examinations for one year was 51.29±4.73 and 99.62±7.36 for new-born males and females, respectively. The lifetime cancer risk decreased with age and reached 3.77±0.62 and 4.88±0.07 for 80-year men and women, respectively. The average lifetime risks of mortality due to cancers induced by annual radiographies were obtained at 14.18±1.62 and 22.83±2.55 for new-born males and females, respectively. This risk reduced with age and was reached 1.97±0.27 and 2.45±0.38 for men and women at the age of 80 years, respectively. Conclusion: Our results showed that there are low but significant risks of cancer incidence for patients undergoing digital radiography, which included a large percentage of the population in Mazandaran province, especially for children and newborns. Therefore, further efforts like appropriate patient setup and beam geometry should be carried out to decrease patient doses.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49630876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background: This work aimed at studying the protective effect of melatonin (MLT) against cypermethrin or γ-radiation induced testicular damage. Material and Methods: Thirty six Male rats were randomly divided into 6 groups. Control group, group treated with MLT (10 mg/Kg b. wt.), group administered cypermethrin (25 mg/ kg. b. wt.), group 4 was exposed to fractionated whole body γ-radiation (the sum=8 Gy), group 5 was coadministered with MLT (10 mg/Kg .b. wt.) and cypermethrin (25 mg/kg b. wt.) and finally group 6 rats were supplemented with MLT (10 mg/Kg .b. wt.) and subsequently administered fractionated γ-radiation(the sum=8 Gy). After treatment for 29 successive days, all animals groups were investigated for hormonal assay, sperm quality, oxidative indices and histological examination of testicular tissues. Results: Rat’s treatment with -radiation or Cypermethrin showed a significant decrease in body weight, testis, epididymis, ventral prostate and seminal-vesicles weights. Also, a significant increase was observed in the levels of TBARS and H2O2, while a significant reduction occurred in the activity of SOD, CAT and GSH content in testis tissues, in addition to a significant decrease in testosterone hormone. On the other hand, a significant increase occurred in FSH and prolactin hormones .moreover, a significant decrease in sperm count and motility occured beside a significant increase in abnormal forms. Pretreatment of rats with MLT improved the disturbances induced in the tested parameters of rats either received cypermethrin or γ-irradiation. Conclusion: According to the present findings, the ameliorative role of MLT is obvious against cypermethrin or γ-irradiation induced testicular damage probably, due to its antioxidative properties.
{"title":"Ameliorative role of melatonin against cypermethrin or gamma irradiation induced testicular damage in male rats","authors":"E. M Kamal El-Dein, Lobna M. Anees","doi":"10.52547/IJRR.18.4.765","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.765","url":null,"abstract":"Background: This work aimed at studying the protective effect of melatonin (MLT) against cypermethrin or γ-radiation induced testicular damage. Material and Methods: Thirty six Male rats were randomly divided into 6 groups. Control group, group treated with MLT (10 mg/Kg b. wt.), group administered cypermethrin (25 mg/ kg. b. wt.), group 4 was exposed to fractionated whole body γ-radiation (the sum=8 Gy), group 5 was coadministered with MLT (10 mg/Kg .b. wt.) and cypermethrin (25 mg/kg b. wt.) and finally group 6 rats were supplemented with MLT (10 mg/Kg .b. wt.) and subsequently administered fractionated γ-radiation(the sum=8 Gy). After treatment for 29 successive days, all animals groups were investigated for hormonal assay, sperm quality, oxidative indices and histological examination of testicular tissues. Results: Rat’s treatment with -radiation or Cypermethrin showed a significant decrease in body weight, testis, epididymis, ventral prostate and seminal-vesicles weights. Also, a significant increase was observed in the levels of TBARS and H2O2, while a significant reduction occurred in the activity of SOD, CAT and GSH content in testis tissues, in addition to a significant decrease in testosterone hormone. On the other hand, a significant increase occurred in FSH and prolactin hormones .moreover, a significant decrease in sperm count and motility occured beside a significant increase in abnormal forms. Pretreatment of rats with MLT improved the disturbances induced in the tested parameters of rats either received cypermethrin or γ-irradiation. Conclusion: According to the present findings, the ameliorative role of MLT is obvious against cypermethrin or γ-irradiation induced testicular damage probably, due to its antioxidative properties.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49042914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Rostami, S. Naseri, M. Momennezhad, H. Zare, K. Anvari, H. R. S. Badkhor
Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distortion by a new large field of view phantom. Materials and Methods: A homemade phantom with Perspex sheets and plastic pipes containing water was built for evaluating MR images distortion. The phantom size is 48×48×37 cm and includes 325 water pipes. The study evaluated four different protocols from a 60 cm bore MAGNETOM® Symphony Syngo 1.5 T (Siemens). Results: It was found that the amount of distortion for all protocols is under 2 mm for the radial distances less than 10 cm (field of view (FOV) = 20 cm), but distortion increased in radial distances greater than 10 cm, and reached about 5 cm for radial distances greater than 25 cm. Conclusion: Geometric distortion of each MR scanner has been shown to be dependent on the radio frequency (RF) sequence pulse (Spin echo or Gradient echo) and image parameters (echo time (TE), repetition time (TR), and receiver band-width)). The geometric distortion could be ignored for the FOV<20 cm (for the head region), and must be evaluated and corrected for more FOVs before the MR only radiotherapy.
{"title":"Geometric distortion evaluation of magnetic resonance images by a new large field of view phantom for magnetic resonance based radiotherapy purposes","authors":"A. Rostami, S. Naseri, M. Momennezhad, H. Zare, K. Anvari, H. R. S. Badkhor","doi":"10.52547/IJRR.18.4.733","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.733","url":null,"abstract":"Background: The magnetic resonance imaging (MRI)-based radiotherapy planning method have been considered in recent years because of the advantages of MRI and the problems of planning with two images modality. The first step in MRI-based radiotherapy is to evaluate magnetic resonance (MR) images geometric distortion. Therefore, the present study aimed to evaluate system related geometric distortion by a new large field of view phantom. Materials and Methods: A homemade phantom with Perspex sheets and plastic pipes containing water was built for evaluating MR images distortion. The phantom size is 48×48×37 cm and includes 325 water pipes. The study evaluated four different protocols from a 60 cm bore MAGNETOM® Symphony Syngo 1.5 T (Siemens). Results: It was found that the amount of distortion for all protocols is under 2 mm for the radial distances less than 10 cm (field of view (FOV) = 20 cm), but distortion increased in radial distances greater than 10 cm, and reached about 5 cm for radial distances greater than 25 cm. Conclusion: Geometric distortion of each MR scanner has been shown to be dependent on the radio frequency (RF) sequence pulse (Spin echo or Gradient echo) and image parameters (echo time (TE), repetition time (TR), and receiver band-width)). The geometric distortion could be ignored for the FOV<20 cm (for the head region), and must be evaluated and corrected for more FOVs before the MR only radiotherapy.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42573348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Jiang, Xinghuan Wang, Z. Dai, Jiuling Shen, Dajiang Wang, Z. Bao, Chen Chen, Hongli Zhao, Jun Chen, C. Xie, Junhong Zhang, Hui Liu
Background: This paper aimed to analyze the output constancy of a medical linear accelerator using PTW QUICKCHECK and studied the sensitivity of the PTW QUICKCHECK. Materials and Methods: The paper statistically analyzed the output doses of 6 MV and 10 MV of photons and 6 MeV, 9 MeV, and 12 MeV of electrons from a medical linear accelerator measured before the daily treatment to assess the output stability of a medical linear accelerator. Some modifications were introduced by artificially altering the external irradiation conditions, and the percent variations from baseline values were noted. The gantry angle was changed and some deviations were established in the vertical, longitudinal and lateral directions to study the sensitivity of the PTW QUICKCHECK. The beam flatness, symmetry, radiation quality and output energy of 6 MV of photon energy were statistically analyzed. Results: Among the measurements, no parameters exceeded the tolerance of ±3%. QUICKCHECK was capable of detecting the variations in the central axis dose, flatness, symmetry and radiation quality under the testing conditions. Similar to the photon energy, electron energy measurements also confirmed that the detector was sensitive to a small variation in output introduced by the testing conditions. An important application of accelerator performance prediction in this study confirms the irreplaceable and important function of morning quality checks of a linear accelerator. Conclusions: The output dose measured before daily treatment using PTW QUICKCHECK to analyze the linear accelerator output constancy helps to decrease the system error, effectively reduces the errors of the accelerator system, and avoids serious mistakes.
{"title":"Systematic and comprehensive analysis of the dose-response characteristics of a morning quality check of a linear accelerator and an important application of accelerator performance prediction","authors":"D. Jiang, Xinghuan Wang, Z. Dai, Jiuling Shen, Dajiang Wang, Z. Bao, Chen Chen, Hongli Zhao, Jun Chen, C. Xie, Junhong Zhang, Hui Liu","doi":"10.52547/IJRR.18.4.841","DOIUrl":"https://doi.org/10.52547/IJRR.18.4.841","url":null,"abstract":"Background: This paper aimed to analyze the output constancy of a medical linear accelerator using PTW QUICKCHECK and studied the sensitivity of the PTW QUICKCHECK. Materials and Methods: The paper statistically analyzed the output doses of 6 MV and 10 MV of photons and 6 MeV, 9 MeV, and 12 MeV of electrons from a medical linear accelerator measured before the daily treatment to assess the output stability of a medical linear accelerator. Some modifications were introduced by artificially altering the external irradiation conditions, and the percent variations from baseline values were noted. The gantry angle was changed and some deviations were established in the vertical, longitudinal and lateral directions to study the sensitivity of the PTW QUICKCHECK. The beam flatness, symmetry, radiation quality and output energy of 6 MV of photon energy were statistically analyzed. Results: Among the measurements, no parameters exceeded the tolerance of ±3%. QUICKCHECK was capable of detecting the variations in the central axis dose, flatness, symmetry and radiation quality under the testing conditions. Similar to the photon energy, electron energy measurements also confirmed that the detector was sensitive to a small variation in output introduced by the testing conditions. An important application of accelerator performance prediction in this study confirms the irreplaceable and important function of morning quality checks of a linear accelerator. Conclusions: The output dose measured before daily treatment using PTW QUICKCHECK to analyze the linear accelerator output constancy helps to decrease the system error, effectively reduces the errors of the accelerator system, and avoids serious mistakes.","PeriodicalId":14498,"journal":{"name":"Iranian Journal of Radiation Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45615029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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