• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.488-498
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• 2003

Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.11-15
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• 1999

To investigate the stimulating effects of the low- dose radiation, the seeds of chinese cabbages (Brassica campestris L. cv. Hanyoreum and cv. Tropic emperor) were irradiated at the dose of 0.5 Gy~20 Gy with the ${\gamma}$-ray radition. In case of ‘Hanyoreum’cultivar, there were no significant promoting effects on the germination rate except the 0.5 Gy irradiated group. The increase in seedling height and fresh weight in 8 Gy and 12 Gy irradiated groups was 20% and 40%, respectively, which suggested the stimulating effect of the low-dose radiation on the early growth. In case of‘Tropic emperor’cultivar, the germination rate of 1 Gy irradiated group increased approximately 10% and the seedling height and fresh weight of 1 Gy and 12 Gy irradiated group in the greenhouse 20% on the average, and plant height and fresh weight of 0.5 Gy and 4 Gy irradiated group in the field increased 10% and 20% on the average, respectively.

• Journal of the Korean Society of Radiology
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• v.13 no.2
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• pp.233-239
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• 2019

The purpose of this study was to investigate the knowledge and awareness about radiation use among non - radiation undergraduates. This analysis were used based on the collected questionnaires with Frequency, mean and standard deviation, t-test, one-way ANOVA. As a result, there was no significant difference between the groups in terms of gender and age. There were statistical differences in some items in the major field. In addition, the perception of radiation was more negative in women and under 25 years of age (p<0.05). The correlations between the sub - factors showed that the higher the knowledge of radiation, the higher the perception of knowledge and use of radiation. It is believed that university students will have a positive effect of contributing to the development of the radiation industry if they have a correct understanding of radiation because they are more likely to contribute to public opinion by advancing into society.

• Korean Journal of Environmental Biology
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• v.29 no.1
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• pp.61-67
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• 2011

N-acetyl-L-cysteine (NAC) having a thiol, a precursor for glutathione (GSH), is known as one of the antioxidants. NAC used as a radioprotector against ionizing radiation (IR)-induced injury and damage. The aim of this study was to evaluate the radioprotective effects of NAC against IR-induced cell damage in Saccharomyces cerevisiae and the antioxidative effect of NAC on transcriptional level of yeast antioxidant enzyme genes such as superoxide dismutase (SOD) and catalase. In the present study, yeast cells were pretreated with various concentrations of NAC and/or irradiated with various doses of gamma rays. The cell viability was measured by counting the cell forming unit (CFU). The quantitative real-time PCR was performed for analysis of gene expression of SOD and catalase. The viability of irradiated cells was not improved by pretreatment with NAC. Ionizing radiation with 100 Gy highly induced the gene expression of antioxidant enzymes. In the irradiated group with NAC pretreatment, the gene expression of SOD and catalase was gradually reduced with the increased concentrations of NAC. These results indicate that NAC can act as a useful antioxidant to scavenge reactive oxygen species in vivo, but does not protect cells against IR-induced cell death in S. cerevisiae.

• Journal of Nutrition and Health
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• v.42 no.7
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• pp.605-614
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• 2009

Most cancer patients are treated with surgery, chemotherapy or radiation as anticancer therapies. Especially in the case of radiation, these treatments produce adverse effects such as vomiting, weight loss, anorexia, normal cell damage and malabsorption. The major goal of this study was to determine the effect of irradiation on the nutritional and immune status in irradiated rats. A secondary goal was to determine the effectiveness of high protein diet (HP) and resveratrol (Res) in minimizing the adverse effects of radiation. Rats were divided into four groups: normal diet (NP), HP, NP + Res and HP + Res groups. Each group was further divided into subgroups that received radiation (RT group) and one that did not (non-RT group). Each diet was supplied from $12^{th}$ day prior to irradiation treatment with irradiation dose of 17.5 Gy. The diets were continued until 10th day after radiation treatment and animals were sacrificed. The radiation treatment showed decreased body weight, serum protein and HDL levels and increased TG and LDL levels in nutritional status. HP, NP + Res and HP + Res groups reduced the level of serum LDL and TG in irradiated rats. NP + Res and HP + Res groups increased reduced albumin level of serum in RT group. In case of immune status, the radiation treat-ment showed decreased WBC, lymphocytes and increased neutrophil and eosinophil levels. The levels of serum IL-2 and IL-6 were significantly increased by radiation, however the cytokine levels decreased in all dietary treatment groups. These results showed that high protein diet and resveratrol supplementation seem to minimize the adverse effects of radiation on lipid nutritional status and inflammation response in the rat model.

• Radiation Oncology Journal
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• v.22 no.1
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• pp.40-54
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• 2004

Purpose : Captopril (angiotension converting enzyme inhibitor) is known to have a radioproptective effect in the lungs, intestines and skin, but its effect in the heart is unclear. To investigate the radioprotectlve efiect and mechanism of captopril on the heart, the histopathological changes and immunohistochemical stains were compared with radiation alone, and radiation combined with captopril, in the rats. Materials and Methods : The histopathological changes and immunohistochemical stains ($TNF{\alpha}$, $TGF{\beta}1$, PDGF and FGF2) were examined in the radiation alone and the combined captopril and radiation groups, 2 and 8 weeks after irradiation. Each group consisted of 8 to 10 rats (Sprague-Dawley). Irradiation (12.5 Gy) was given to the left hemithorax in a single fraction. Captopril (50 mg/Kg/d) mixed with water, was given orally and continuously from the first week prior to, up to the 8th week of the experiment. Results : In the radiation alone group, the ventricle at 2 weeks after irradiation showed prominent edema (p=0.082) and fibrin deposit (p=0.018) compared to the control group. At 8 weeks, the edema was decreased and fibrosis increased compared to those at 2 weeks. The histopathological changes of the combined group were similar to those of the control group, due to the reduced radiation toxicity at 2 and 8 weeks. The endocardial fibrin deposit (p=0.047) in the atrium, and the interstitial fibrin deposit (p=0.019) and edema (p=0.042) of the ventricle were reduced significantly in the combined group compared to those in the radiation alone group at 2 weeks. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$, PDGF and FGF-2 in the radiation alone group were more increased than in the control group, especially in the pericardium and endocardium of the atrium at 2 weeks. At 8 weeks, the pericardial $TNF-{\alpha}$ and $TGF-{\beta}1$ in the radiation alone group continuously increased. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$ and PDGF were decreased in the combined group at 2 weeks. At 8 weeks, the expressions of $TNF-{\alpha}$ in the atrial and ventricular pericardia were markedly reduced (p=0.049, p=0.009). Conclusion : This study revealed that the early heart damage induced by radiation can be reduced by the addition of captopril in a rat model. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$ and PDGF were further decreased in the combined compared to the radiation alone group at both 2 and 8 weeks. From these results, it may be concluded that these cytokines probably play roles in the radioprotective mechanism of captopril from the radiation-induced heart toxicity, similarly to in other organs.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.45-52
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• 2001

Purpose : Granulocyle-colony stimulating factor (G-CSF) has been widely used to treat neutropenia caused by chemotherapy or radiotherapy. The efficacy of recombinant human hematopoietic growth factors in improving oral mucositis after chemotherapy or radiotherapy has been recently demonstrated in some clinical studies. This study was designed to determine whether G-CSF can modify the radiation injury of the intestinal mucosa in mice. Materials and Methods : One hundred and five BALB/c mice weighing 20 grams were divided into nine subgroups including G-CSF alone group $(I:10\;{\mu}g/kg\;or\;II:100\;{\mu}g/kg)$, radiation alone group (7.5 or 12 Gy on the whole body), combination group with G-CSF and radiation (G-CSF I or II plus 7.5 Gy, G-CSF I or II plus 12 Gy), and control group. Radiation was administered with a 6 MV linear accelerator (Mevatron Siemens) with a dose rate of 3 Gy/min on day 0. G-CSF was injected subcutaneously for 3 days, once a day, from day -2 to day 0. Each group was sacrificed on the day 1, day 3, and day 7. The mucosal changes of jejunum were evaluated microscopically by crypt count per circumference, villi length, and histologic damage grading. Results : In both G-CSF I and II groups, crypt counts, villi length, and histologic damage scores were not significantly different from those of the control one (p>0.05). The 7.5 Gy and 12 Gy radiation alone groups showed significantly lower crypt counts and higher histologic damage scores compared with those of control one (p<0.05). The groups exposed to 7.5 Gy radiation plus G-CSF I or II showed significantly higher crypt counts and lower histologic damage scores on the day 3, and lower histologic damage scores on the day 7 compared with those of the 7.5 Gy radiation alone one (p<0.05). The 12 Gy radiation plus G-CSF I or II group did not show significant difference in crypt counts and histologic damage scores compared with those of the 12 Gy radiation alone one (p>0,05). Most of the mice in 12 Gy radiation with or without G-CSF group showed intestinal death within 5 days. Conclusion : These results suggest that G-CSF may protect the jejunal mucosa from the acute radiation damage following within the tolerable ranges of whole body irradiation in mice.

• Radiation Oncology Journal
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• v.25 no.1
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• pp.7-15
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• 2007

[ $\underline{Purpose}$ ]: To determine the patterns of evaluation and treatment in patients with breast cancer after mastectomy and treated with radiotherapy. A nationwide study was performed with the goal of improving radiotherapy treatment. $\underline{Materials\;and\;Methods}$: A web- based database system for the Korean Patterns of Care Study (PCS) for 6 common cancers was developed. Randomly selected records of 286 eligible patients treated between 1998 and 1999 from 17 hospitals were reviewed. $\underline{Results}$: The ages of the study patients ranged from 20 to 80 years (median age 44 years). The pathologic T stage by the AJCC was T1 in 9.7% of the cases, T2 in 59.2% of the cases, T3 in 25.6% of the cases, and T4 in 5.3% of the cases. For analysis of nodal involvement, N0 was 7.3%, N1 was 14%, N2 was 38.8%, and N3 was 38.5% of the cases. The AJCC stage was stage I in 0.7% of the cases, stage IIa in 3.8% of the cases, stage IIb in 9.8% of the cases, stage IIIa in 43% of the cases, stage IIIb in 2.8% of the cases, and IIIc in 38.5% of the cases. There were various sequences of chemotherapy and radiotherapy after mastectomy. Mastectomy and chemotherapy followed by radiotherapy was the most commonly performed sequence in 47% of the cases. Mastectomy, chemotherapy, and radiotherapy followed by additional chemotherapy was performed in 35% of the cases, and neoadjuvant chemoradiotherapy was performed in 12.5% of the cases. The radiotherapy volume was chest wall only in 5.6% of the cases. The volume was chest wall and supraclavicular fossa (SCL) in 20.3% of the cases; chest wall, SCL and internal mammary lymph node (IMN) in 27.6% of the cases; chest wall, SCL and posterior axillary lymph node in 25.9% of the cases; chest wall, SCL, IMN, and posterior axillary lymph node in 19.9% of the cases. Two patients received IMN only. The method of chest wall irradiation was tangential field in 57.3% of the cases and electron beam in 42% of the cases. A bolus for the chest wall was used in 54.8% of the tangential field cases and 52.5% of the electron beam cases. The radiation dose to the chest wall was $45{\sim}59.4\;Gy$ (median 50.4 Gy), to the SCL was $45{\sim}59.4\;Gy$ (median 50.4 Gy), and to the PAB was $4.8{\sim}38.8\;Gy$, (median 9 Gy) $\underline{Conclusion}$: Different and various treatment methods were used for radiotherapy of the breast cancer patients after mastectomy in each hospital. Most of treatment methods varied in the irradiation of the chest wall. A separate analysis for the details of radiotherapy planning also needs to be followed and the outcome of treatment is needed in order to evaluate the different processes.

• Radiation Oncology Journal
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• v.24 no.3
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• pp.179-184
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• 2006

[ $\underline{Purpose}$ ]: To explore the effect of recombinant human EGF on the proliferation and survival of human fibroblast cell lines following irradiation. $\underline{Materials\;and\;Methods}$: Fibroblast was originated human skin and primary cultured. The trypan blue stain assay and MTT assay were used to study the proliferative effects of EGF on human fibroblast cell lines in vitro. An incubation of fibroblasts with rhEGF for 24 hours immediately after irradiation was counted everyday. Cell cycle distributions were analyzed by FACS analysis. $\underline{Results}$: Number of fibroblast was significantly more increased rhEGF (1.0 nM, 10 nM, 100 nM, 1,000 nM) treated cell than control after 8 Gy irradiation. Most effective dose of rhEGF was at 160 nM. These survival differences were maintained at 1 week later. Proportion of S phase was significantly increased on rhEGF treated cells. $\underline{Conclusion}$: rhEGF cause increased fibroblast proliferation following irradiation. We expect that rhEGF was effective for radiation induced wound healing.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.289-293
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• 1988

Radiation therapy has been used as adjuvant therapy or primary treatment for inoperable, remnant or recurrent cancer. Many authors reported good palliation effect by external irradiation or interstitial therapy, but the report of intracavitary irradiation for recurrent, inoperable rectal cancer is very rare. We experienced a case of recurrent adenocarcinoma of rectum along fistula tract after laparotomy and postoperative radiotherapy who achieved very good palliation by intracavitary irradiation. Even though we have only good palliation without impressive survival improvement in this case, we hope that this technique may achieve good local control In other similar patients.