• Radiation Oncology Journal
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• v.14 no.2
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• pp.115-122
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• 1996

Purpose : To improve the treatment results of locally advanced nonsmall cell lung cancer (NSCLC) patients we treated those patients with regional hyperthermia combined with radiotherapy. And we conducted a retrospective analysis of the results. Material and Methods Thirty two nonsmall cell lung cancer Patients treated at the Department of Radiation Oncology, St. Mary's hospital, Catholic University Medical College were the base of this analysis. Fourteen patients of above them were treated with hyperthermia and radiotherapy of more than 3000 cGy in radiation dose. Radiofrequency capacitive hyperthermia was administered twice weekly immediately after radiotherapy. Total sessions of hyperthermia ranged from 3 to 13 times (mean 7.8). Eighteen patient received an external radiation therapy alone Median radiation dose was 5580 cGy (range, 3000-7000 cGy) in fraction of 180-300 cGy, 5 fractions per week. Results: The results of themoradiotherapy group (HTRT group) were compared with radiation alone group (RT group). There were no complete response (CR) and 12 Partial responses (PR) (CR rate $0\%$, response rate $85.7\%$) in HTRT group, whereas there were 2 CRs, 8 PRs and 8 no responses (CR rate $11.1\%$, response rate $55.6\%$) in RT group. There was significant differece in local response rate of the tumors between RT group and HTRT group (p < 0.05). Overall 2 rear survival rate and mean survival were $7.1\%$ and 10.5 months for HTRT group, and $0\%$ and 8.1 months for RT group. However, by the number of hyperthermia. in cases with more than or equal to 10 sessions of hyperthermia, there were significant improvement in 2 year year survival rate and mean survival ($40.0\%$ and 18.2 months) compared with those in cases with less than 10 sessions of hyperhtemia ($7.4\%$ and 7.4 months) (p < 0.05). Conclusion : Thermoradiotherapy in locally advanced NSCLC patients increased their response rate but not 2 year survival and mean survival, therefore thermoradiotherpy with enough number of hyperthermia is suggested that may be one of the effective palliative treatments of those patients. And in cases with more than 10 sessions of hyperthermia, there showed improved 2 year survival rate and mean survival But the number of the cases was small further study in this aspect is required.

• Nuclear Engineering and Technology
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• v.33 no.6
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• pp.626-637
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• 2001

A series of study on energy dependence in chemiluminescence dosimetry with sugar and sorbite produced in two different countries was carried out administering a dose of 5 Gy to the samples at six different mean photon energies of 30, 50, 80, 130, 662 and 1250 keV. The results revealed distinct energy dependence of chemiluminescence(CL) output of sugar and sorbite. Although the energy dependence, in general, could be fitted by a polynomial of (os E, with I being radiation energy, up to cubic term, we reached a conclusion that the adoption of a fitting function, $y_{R}$$^{=a}$.(1-e $^{-b.logE}$)$^{c}$ +d, deduced from theoretical energy response curve calculated as the ratio of the mass energy absorption of the samples of interest to the soft tissue is more reasonable and rational. Herecoefficients $y_{R}$ is CL intensity, and a, b, c and d are constants to be determined in the fitting process. Energy dependence of relative sensitivities of one sample to the other, discrepancy in sensitivities of the samples from the two countries, and prominent grain size effect in Sorbitol were also shown.shown.

• Korean Journal of Soil Science and Fertilizer
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• v.4 no.1
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• pp.33-40
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• 1971

Using radioactive $^{40}K$ in potassium, a study was conducted to evaluate the potassium supplying power of different soil types developed on different parent materials. A conversion factor based on two parameters namely $\frac{available\;K_{soil}}{total\;K_{soil}}$ and $\frac{K_{plant}}{K_{soil}}$ was developed and found to be closely related to plant response. According to this characterization soils derived from the various parent materials were ranked as basalt >Silla series>gneiss>porphyry>granite${\gg}$schist. From the point of view of potassium response as measured by yield as similar response pattern was observed. That is, soils derived from basalt to be most responsive as compared to the other soils. The variations among the soils may be accounted for to their potassium bearing mineralogical composition and their stability.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.255-261
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• 2022

A reliable and well-characterized dosimetry system which is traceable to the international measurement system, is the key element to quality assurance in radiation processing with cobalt-60 gamma rays, X-rays, and electron beam. This is specifically the case for health-regulated processes, such as the radiation sterilization of single use medical devices and food irradiation for preservation and disinfestation. Polyethylene is considered to possess a lot of interesting dosimetric characteristics. In this work, a detailed study has been performed to determine the dosimetric characteristics of a commercialized high-density polyethylene (HDPE) film using Fourier transformed infrared spectrometry (FTIR). Correlations have been established between the absorbed dose and radiation induced infrared absorption in polyethylene having a maximum at 965 cm^-1 (transvinylene band) and 1716 cm^-1 (ketone-carbonyl band). We have found that polyethylene dose-response is linear with dose for both bands up to1000 kGy. For transvinylene band, the dose-response is more sensitive if irradiations are made in helium. While, for ketone-carbonyl band, the dose-response is more sensitive when irradiations are carried out in air. The dose-rate effect has been found to be negligible when polyethylene samples are irradiated with electron beam high dose rates. The irradiated polyethylene is relatively stable for several weeks after irradiation.

• Radiation Oncology Journal
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• v.36 no.1
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• pp.17-24
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• 2018

Purpose: This study aimed to assess complications and outcomes of a new approach, that is, combining short course radiotherapy (SRT), concurrent and consolidative chemotherapies, and delayed surgery. Materials and Methods: In this single arm phase II prospective clinical trial, patients with T3-4 or N+ M0 rectal adenocarcinoma were enrolled. Patients who received induction chemotherapy or previous pelvic radiotherapy were excluded. Study protocol consisted of three-dimensional conformal SRT (25 Gy in 5 fractions in 1 week) with concurrent and consolidation chemotherapies including capecitabine and oxaliplatin. Total mesorectal excision was done at least 8 weeks after the last fraction of radiotherapy. Primary outcome was complete pathologic response and secondary outcomes were treatment related complications. Results: Thirty-three patients completed the planned preoperative chemoradiation and 26 of them underwent surgery (24 low anterior resection and 2 abdominoperineal resection). Acute proctitis grades 2 and 3 were seen in 11 (33.3%) and 7 (21.2%) patients, respectively. There were no grades 3 and 4 subacute hematologic and non-hematologic (genitourinary and peripheral neuropathy) toxicities and perioperative morbidities such as anastomose leakage. Grade 2 or higher late toxicities were observed among 29.6% of the patients. Complete pathologic response was achieved in 8 (30.8%) patients who underwent surgery. The 3-year overall survival and local control rates were 65% and 94%, respectively. Conclusion: This study showed that SRT combined with concurrent and consolidation chemotherapies followed by delayed surgery is not only feasible and tolerable without significant toxicity but also, associated with promising complete pathologic response rates.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.1-8
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• 1994

When cells are exposed to low doses of a mutagenic or clastogenic agents. they often become less sensitive to the effects of a higher dose administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher dose (50 cGy), The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines, which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism.

• Radiation Oncology Journal
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• v.38 no.2
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• pp.93-98
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• 2020

Purpose: Due to COVID 19 pandemic, the treatment of cancer patients has become a dilemma for every oncologist. Cancer patients are at an increased risk of immunosuppression and have a higher risk to acquire any infection. There are individual experiences from some centers regarding the management of cancer patients during such a crisis. So we have developed our institutional strategy to balance between COVID and cancer management. Materials and Methods: Radiation Oncology departmental meeting was held to prepare a consensus document on Radiotherapy schedules and department functioning during this pandemic. Results: Strategies were taken in form of following areas were steps need to be taken to decrease risk of infection, categorise treatment on the basis of priority, radiotherapy schedules modification, academic meetings and management of COVID positive patient/personnel in Radiation Oncology department. Conclusion: We hope to strike the balance in overcoming both the battles and emerge as winners. Stringent long term follow up will be done for assessing the response or any unforeseen treatment related sequelae.

• Journal of Radiation Industry
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• v.2 no.1
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• pp.1-7
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• 2008

Active polymer gels expand and contract in response to certain environmental stimuli, such as the application of an electric field or a change in the pH level of the surroundings. This ability to achieve large, reversible deformations with no external mechanical loading has generated much interest in the use of these gels as biomimetic actuators and artificial muscles. In this study, poly (vinyl alcohol)(PVA) grafted acrylic acid monomer (PVA-g-AAc) hydrogels were prepared by $^{60}Co$ ${\gamma}-ray$ irradiation and their properties such as degree of grafting and weight swelling in electrostimulation as an artificial muscle and actuator were investigated.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.201-207
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• 1994

To objectively compare the response of the palliative radiotherapy in bone metastatic patients which decreases pain and prevents pathologic fractures, we introduced and applied the RTOG pain and narcotic measure system. From Oct in 1991 to July in 1993, thirty-two patients with painful bone metastases, 17 of them were solitary lesions and others were multiple lesions, were treated with mainly 6 MV photon otherwise 15 MV photon. Radiation doses to bone metastatic sites ranged about from 2000 to 4600cGy. Responses of radiation therapy were compared with days of pre-RT, RT finish, 3, 6, 9 months after the start of RT and solitary versus multiple lesions and follow up scores according to the RTOG measure system. Survival analysis was done. Pain and narcotic score of the entire patients were 7.3, 7.8 at the pre-RT period and 2.6, 3.9 at the immediate or 2 weeks after RT, which was $64{\%},\;50{\%}$ decrement compared with the pre-RT score, Pain scores of 3, 6 and 9 months after the beginning of irradiation were 3.6, 3.7 and 3.3. The best response found in the breast and prostate primaries was $84\%,\;78\%$ decrement of pain score as compared with pre-RT score(statistically insignificant). Median survival was 5.5 months and mean survival was 5 months. We conclude that the RTOG pain and narcotic measure system is relatively effective scale in the comparison of before and after palliative irradiation to the painful bone metastatic sites but more detailed parameters will be required in the narcotic scoring system. More aggressive but less or similiar toxic radiotherapy is needed in the patients having relatively long life expected time.

• Radiation Oncology Journal
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• v.11 no.1
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• pp.119-126
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• 1993

From 1988 to 1991, nineteen patients with unresectable localized pancreatic carcinoma were treated with radiotherapy and/or hyperthermia or in combination with chemotherapy. Radiation dose of 4500-5000 cGy with or without additional 500-1000 cGy was administered over 5 to 6 weeks to the pancreatic tumor area using 10 MV linear accelerator. Five of 19 patients were given chemotherapy, either neoadjuvant or maintenance setting with FAM regimen (5-FU, adriamycin and mitomycin C), which was repeated every 4 weeks for one year or until progression. Symptomatic palliation was achieved in 17 among 19 patients ($89{\%}$) and objective response (complete or partial response in CT finding) was achieved in 5 among 11 patients ($45{\%}$). The median survival time was 9 months and one-year survival rate, $32{\%}$. Local-regional failure was documented in 10 among 13 patients ($77{\%}$) and distant failures were found in the liver (3 patients) and carcinomatosis (2 patients). Prognostic significance of various factors such as age, sex, performance status, tumor location, stage, etc. were assessed. Any factors did not have the prognostic significance in univariate analysis. Treatment was well tolerated in most of the patients with only mild to moderate toxicity.