• Title/Summary/Keyword: IR radiation

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Combined Treatment with 2-Deoxy-D-Glucose and Doxorubicin Enhances the in Vitro Efficiency of Breast Cancer Radiotherapy

  • Islamian, Jalil Pirayesh;Aghaee, Fahimeh;Farajollahi, Alireza;Baradaran, Behzad;Fazel, Mona
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8431-8438
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    • 2016
  • Doxorubicin (DOX) was introduced as an effective chemotherapeutic for a wide range of cancers but with some severe side effects especially on myocardia. 2-Deoxy-D-glucose (2DG) enhances the damage caused by chemotherapeutics and ionizing radiation (IR) selectively in cancer cells. We have studied the effects of $1{\mu}M$ DOX and $500{\mu}M$ 2DG on radiation induced cell death, apoptosis and also on the expression levels of p53 and PTEN genes in T47D and SKBR3 breast cancer cells irradiated with 100, 150 and 200 cGy x-rays. DOX and 2DG treatments resulted in altered radiation-induced expression levels of p53 and PTEN genes in T47D as well as SKBR3 cells. In addition, the combination along with IR decreased the viability of both cell lines. The radiobiological parameter (D0) of T47D cells treated with 2DG/DOX and IR was 140 cGy compared to 160 cGy obtained with IR alone. The same parameters for SKBR3 cell lines were calculated as 120 and 140 cGy, respectively. The sensitivity enhancement ratios (SERs) for the combined chemo-radiotherapy on T47D and SKBR3 cell lines were 1.14 and 1.16, respectively. According to the obtained results, the combination treatment may use as an effective targeted treatment of breast cancer either by reducing the single modality treatment side effects.

Dose Evaluation of the Man Adjacent to an Implanted Patient During the Prostate Cancer Brachytherapy (전립선암의 근접치료 시 이식환자에 근접한 사람의 선량평가)

  • Park, Euntae;Kim, Junghoon
    • Journal of the Korean Society of Radiology
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    • v.10 no.1
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    • pp.39-44
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    • 2016
  • This study is fulfilled to evaluate the exposure dose nearby a patient during the brachytherapy of the prostate cancer treatment and to minimize the radiation exposure by evaluating the exposure dose of the person near the relevant implanted patient, technicians and gardians. The experiment method is used on the study is MCNPX that is stood on the basis monte-carlo method and implant the source to MIRD-type phantom in $^{192}Ir$, $^{125}I$, and $^{103}Pd$ in virtual space. For dose evaluations according to distance, the radiation dose on the patient near the corresponding implanted patient is evaluated by each distance of 30, 50, 100, 200 cm to anterior from the implanted patient. As a result, $^{192}Ir$ showed a higher dose than $^{125}I$ and $^{103}Pd$ in every distance.

Derivation of External Exposure Characteristics of Industrial Radiography Based on Empirical Evidence

  • Cho, Junik;Kim, Euidam;Kwon, Tae-Eun;Chung, Yoonsun
    • Journal of Radiation Protection and Research
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    • v.47 no.2
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    • pp.93-98
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    • 2022
  • Background: This study aims to derive the characteristics of each work type for industrial radiography based on empirical evidence through expert advice and a survey of radiation workers of various types of industrial radiography. Materials and Methods: According to a Korean report, work types of industrial radiography are classified into indoor tests, underground pipe tests, tests in a shielded room (radiographic testing [RT] room test), outdoor field tests, and outdoor large structure tests. For each work type, exposure geometry and radiation sources were mainly identified through the expert advice and workers' survey as reliable empirical evidence. Results and Discussion: The expert advice and survey results were consistent as the proportion of the work types were high in the order of RT room test, outdoor large structure test, underground pipe test, outdoor field test, and indoor test. The outdoor large structure test is the highest exposure risk work type in the industrial radiography. In most types of industrial radiography, radiation workers generally used 192Ir as the main source. In the results of the survey, the portion of sources was high in the order of 192Ir, X-ray generator, 60Co, and 75Se. As the exposure geometry, the antero-posterior geometry is dominant, and the rotational and isotropic geometry should be also considered with the work type. Conclusion: In this study, through expert advice and a survey, the external exposure characteristics for each work type of industrial radiography workers were derived. This information will be used in the reconstruction of organ dose for health effects assessment of Korean radiation workers.

Synergistic Effect of Resveratrol and Radiotherapy in Control of Cancers

  • Kma, Lakhan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6197-6208
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    • 2013
  • Cancers will continue to be a threat to health unless they can be controlled by combinations of treatment modalities. In this review, evaluate the role of resveratrol (RSV) as a radiosensitizing agent was evaluated and underlying mechanisms holistically explored in different cancer models focusing on therapeutic possibilities. The ability of RSV to modify the effect of radiation exposure in normal and cancer cells has indeed been shown quite convincingly, the combination of RSV and IR exhibiting synergistic effects on different cancer cells. This is relevant since controlled exposure to IR is one of the most frequently applied treatments in cancer patients. However, radiotherapy (XRT) treatment regimes are very often not effective in clinical practice as observed in patients with glioma, prostate cancer (PCa), melanoma, for example, largely due to tumour radioresistant properties. Sensitization of IR-induced apoptosis by natural products such as RSV is likely to be relevant in cancer control and treatment. However, all cancers do not respond to RSV+IR in a similar manner. Therefore, for those such as the radioresistant PCa or melanoma cells, the RSV+IR regime has to be very carefully chosen in order to achieve effective and desirable outcomes with minimum toxicity to normal cells. They are reports that the highest concentration of 100 ${\mu}M$ RSV and highest dose of 5 Gy IR are sufficient to kill cells by induction of apoptosis, indicating that RSV is effective in radiosensitizing otherwise radioresistant cells. In general, it has been shown in different cancer cells that RSV+XRT effectively act by enhancing expression of anti-proliferative and pro-apoptotic molecules, and inhibiting pro-proliferative and anti-apoptotic molecules, leading to induction of apoptosis through various pathways, and cell death. If RSV+XRT can suppress the signature of cancer stemness, enhance the radiosensitivity by either targeting the mitochondrial functionality or modulating the tumour necrosis factor-mediated or Fas-FasL-mediated pathways of apoptosis in different cancers, particularly in vivo, its therapeutic use in the control of cancers holds promise in the near future.

Signal Transduction-related Gene Expression Analysis in MCF-7 followed by $\gamma$-radiation (MCF-7 세포주에서$\gamma$선에 의한 세포신호 전달 관련 유전자의 발현 양상의 분석)

  • 박지윤;황창일;박웅양;김진규;채영규
    • Korean Journal of Environmental Biology
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    • v.21 no.1
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    • pp.52-55
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    • 2003
  • There is considerable evidence that ionizing radiation (IR) mediates checkpoint control, repair and cell death. In this study, we have used a high density microarray hybridization approach to characterize the transcriptional response of human breast carcinoma MCF-7 cell line to ${\gamma}$-radiation, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. We found that exposure to ${\gamma}$-ray alters by at least a $log_2$ factor of 1.0 the expression of 115 known genes. Of the 66 genes affected by ${\gamma}$-radiation, 49 are down-regulated. In our results, the cellular response to irradiation includes induction of the c-jun and EGR1 early response genes. The present work has examined potential cytoplasmic signaling cascades that transduce IR-induced signals to the nucleus. 40S ribosomal protein s6 kinase modulates the activities of the mitogen activated protein kinase (MAPK) and c-Jun $NH_2$-terminal kinase (JNK1) cascades in human monocytic leukemia (U937/pREP4) cells. 14-3-3 family members are dimeric phosphoserine -binding proteins that participate in signal transduction and checkpoint control pathways.

Preparation and Characterization of Ionic Permselective Membrane by Radiation Grafting for Vanadium Redox Flow Battery (방사선을 이용한 바나듐 레독스 흐름전지용 이온 투과선택성 분리막의 제조 및 특성 평가)

  • Sohn, Joon-Yong;Song, Ju-Myung;Shin, Junhwa
    • Journal of Radiation Industry
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    • v.7 no.1
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    • pp.61-67
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    • 2013
  • In this study, we developed ionic permselective membrane as a core material of redox flow battery using radiation grafting method. Two ionic permselective membranes, ETFE-g-PSSA and ETFE-g-PVBSA were prepared by radiation grafting with styrene and VBC followed by sulfonation, respectively. We confirmed that the prepared membranes were successfully prepared via FT-IR. The prepared ionic permselcetive membranes were characterized and the performance of the membranes were evaluated as ionic permselective membranes for vanadium redox flow battery.

Effects on G2/M Phase Cell Cycle Distribution and Aneuploidy Formation of Exposure to a 60 Hz Electromagnetic Field in Combination with Ionizing Radiation or Hydrogen Peroxide in L132 Nontumorigenic Human Lung Epithelial Cells

  • Jin, Hee;Yoon, Hye Eun;Lee, Jae-Seon;Kim, Jae-Kyung;Myung, Sung Ho;Lee, Yun-Sil
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.2
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    • pp.119-124
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    • 2015
  • The aim of the present study was to assess whether exposure to the combination of an extremely low frequency magnetic field (ELF-MF; 60 Hz, 1 mT or 2 mT) with a stress factor, such as ionizing radiation (IR) or $H_2O_2$, results in genomic instability in non-tumorigenic human lung epithelial L132 cells. To this end, the percentages of G2/M-arrested cells and aneuploid cells were examined. Exposure to 0.5 Gy IR or 0.05 mM $H_2O_2$ for 9 h resulted in the highest levels of aneuploidy; however, no cells were observed in the subG1 phase, which indicated the absence of apoptotic cell death. Exposure to an ELF-MF alone (1 mT or 2 mT) did not affect the percentages of G2/M-arrested cells, aneuploid cells, or the populations of cells in the subG1 phase. Moreover, when cells were exposed to a 1 mT or 2 mT ELF-MF in combination with IR (0.5 Gy) or $H_2O_2$ (0.05 mM), the ELF-MF did not further increase the percentages of G2/M-arrested cells or aneuploid cells. These results suggest that ELF-MFs alone do not induce either G2/M arrest or aneuploidy, even when administered in combination with different stressors.

Measurements of relative depth dose rates for a brachytherapy Ir-192 sourceusing an organic scintillator fiber-optic radiation sensor (유기 섬광체-광섬유 방사선 센서를 이용한 근접 방사선원 Ir-192의 상대 깊이 선량율 측정)

  • Shin, Sang-Hun;Jang, Kyoung-Won;Cho, Dong-Hyun;Yoo, Wook-Jae;Seo, Jeong-Ki;Lee, Bong-Soo;Moon, Joo-Hyun;Kim, Sin;Park, Byung-Gi
    • Journal of Sensor Science and Technology
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    • v.17 no.6
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    • pp.462-469
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    • 2008
  • In this study, we have fabricated a fiber-optic radiation sensor using an organic scintillator and plastic optical fiber for brachytherapy dosimetry. Also, we have measured relative depth dose rates of Ir-192 source using a fiber-optic sensor and compared them with the results obtained using a conventional EBT film. Cerenkov lights which can be a noise in measuring scintillating light with a fiber-optic sensor are measured and eliminated by using of a background optical fiber. It is expected that a fiber-optic radiation sensor can be used in brachytherapy dosimetry due to its advantages such as a low cost, simple usage and a small volume.

Fabrication of 3D Feed Horn IR Antenna for IR Detector

  • Kim, Kun-Tae;Han, Yong-Hee;Shin, Hyun-Joon;Sung Moon;Park, Jung-Ho
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.4
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    • pp.170-175
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    • 2004
  • A three dimensional feed horn 10${\mu}{\textrm}{m}$ wavelength infrared antenna has been suggested, fabricated and characterized. It was applied to an infrared detector for efficient collecting of IR radiation and for reducing background noise. The horn antenna size was designed for maximum antenna directivity. The 3D feed horn antenna mold was fabricated using rotating and tilted illumination while the antenna plate was constructed by way of electroplating. Antenna characteristics were measured by coupling with a microbolometer. Measurement results indicated that the directivity of the antenna is 16.1㏈ and the background noise is reduced by approximately two times.

Synthesis and Characterization of N,O-Carboxymethylchitosan Hydrogel Crosslinked by γ-ray Irradiation

  • Gwon, Hui-Jeong;Lim, Youn-Mook;An, Sung-Jun;Youn, Min-Ho;Nho, Young-Chang
    • Journal of Radiation Industry
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    • v.2 no.1
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    • pp.15-19
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    • 2008
  • In order to develop a water-solubility and biocompatibility, chemically modified chitosan, N,O-carboxymethylchitosan (NOCC), was synthesized and the NOCC hydrogels were prepared by using ${\gamma}-ray$ irradiation instead of chemical reagents. The FT-IR spectroscopy, swelling behavior, gel content and mechanical property such as gel strength of the hydrogel were measured. When the NOCC solution concentration was 15 wt% and the dose of irradiation was less than 50 kGy, the NOCC hydrogels had an excellent hydrophilicity and exhibited a good swelling behavior and mechanical properties.