• 제목/요약/키워드: initial dose control

검색결과 153건 처리시간 0.024초

Radiotherapy for locally recurrent rectal cancer treated with surgery alone as the initial treatment

  • Tanaka, Hidekazu;Yamaguchi, Takahiro;Hachiya, Kae;Okada, Sunaho;Kitahara, Masashi;Matsuyama, Katsuya;Matsuo, Masayuki
    • Radiation Oncology Journal
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    • 제35권1호
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    • pp.71-77
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    • 2017
  • Purpose: Although the technical developments of radiotherapy have been remarkable, there are currently few reports on the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as initial treatment in this three-dimensional conformal radiotherapy era. Thus, we retrospectively evaluated the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as the initial treatment. Materials and Methods: Thirty-two patients who underwent radiotherapy were enrolled in this study. The dose per fraction was 2.0-3.5 Gy. Because the treatment schedule was variable, the biological effective dose (BED) was calculated. Results: Local control (LC) and overall survival (OS) rates from the completion of radiotherapy were calculated. The 1-, 2-, 3-, 4-, and 5-year LC rates were 51.5%, 24.5%, 19.6%, 19.6%, and 13.1%, respectively. LC rates were significantly higher for the high BED group (${\geq}75Gy_{10}$) than for the lower BED group (<$75Gy_{10}$). All patients who reported pain achieved pain relief. The duration of pain relief was significantly higher for the high BED group than for the lower BED group. The 1-, 2-, 3-, 4-, and 5-year OS rates were 82.6%, 56.5%, 45.2%, 38.7%, and 23.2%, respectively. There was a trend toward higher OS rates in with higher BED group compared to lower BED group. Conclusion: For patients with unresectable locally recurrent rectal cancer treated with surgery alone, radiotherapy is effective treatment. The prescribed BED should be more than $75Gy_{10}$, if the dose to the organ at risk is within acceptable levels.

Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

  • Back, Geum-mun;Park, Sung Ho;Kim, Tae-Hyung
    • 한국의학물리학회지:의학물리
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    • 제28권2호
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    • pp.45-48
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    • 2017
  • This paper evaluated the amount of radiation generated by wedge filters during radiation therapy using a high-energy linear accelerator, and the dose to the worker during wedge replacement. After 10-MV photon beam was irradiated with wedge filter, the wedge was removed from the linear accelerator, and the dose rate and energy spectrum were measured. The initial measurement was approximately 1 uSv/h, and the radiation level was reduced to 0.3 uSv/h after 6 min. The effective half-life derived from the dose rate measurement was approximately 3.5 min, and the influence of AI-28 was about 53%. From the energy spectrum measurements, a peak of 1,799 keV was measured for AI-28, while the peak for Co-58 was not measured in the control room. The peaks for Au-106 and Cd-105 were found only measurement was done without wedge removement from the linear accelerator. The additional doses received by the radiation worker during wedge replacement were estimated to be 0.08-0.4 mSv per year.

정전가미이진탕(正傳加味二陳湯)의 랫드에서의 단회투여독성시험(單回投與毒性試驗) (Single dose toxicity study of Jengjengamiyjintang in rats)

  • 김상찬;권영규;변준석;김한균;변성희
    • 대한한의학방제학회지
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    • 제10권2호
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    • pp.73-83
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    • 2002
  • The single dose toxicity of Jengjengamiyjintang, a herbal drug for duodenal ulcer was evaluated in male and female Sprague-Dawley (SD) rats. Jengjengamiyjintang was once administered to both sexes of rats at the dose levels of 2000, 1000, 500, 250 and 125mg/kg for oral route according to KFDA guidelines for single dose toxicity test (1999-61). In addition, vehicle control group was added in order to compare clinical signs, body weight changes and abnormal necropsy findings. After single administration, clinical signs were observed every twice a day for 14 days and body weights were measured 5 times including initial measurement on day 0. When observation period was over, the animals were sacrificed and macroscopic examination of major organs was conducted. Neither significant clinical signs nor death after administration was observed during the observation periods except for soft feces or diarrhea that were restricted to Day 1 of 2000 and 1000mg/kg-dosing groups. Although some accidental findings such as gross and histopathological changes of lung that were demonstrated in some animals of all experimental groups including vehicle control group, no abnormal necropsy findings and changes of body weight were observed at terminal necropsy in both sexes. From these results, it is considered that $LD_{50}$ of Jengjengamiyjintang is over 2000mg/kg in oral administration in both sexes of rats and approximated lethal dose was considered over 2000mg/kg.

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Large-scale purification and single-dose oral-toxicity study of human thioredoxin and epidermal growth factor introduced into two different genetically modified soybean varieties

  • Jung-Ho, Park
    • 농업과학연구
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    • 제48권4호
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    • pp.1003-1013
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    • 2021
  • Thioredoxin (TRX) protein is an antioxidant responsible for reducing other proteins by exchanging cysteine thiol-disulfide and is also known for its anti-allergic and anti-aging properties. On the other hand, epidermal growth factor (EGF) is an important material used in the cosmetics industry and an essential protein necessary for dermal wound healing facilitated by the proliferation and migration of keratinocytes. EGF also assists in the formation of granulation tissues and stimulates the motility of fibroblasts. Hence, genetically modified soybeans were developed to overexpress these industrially important proteins for mass production. A single-dose oral-toxicity-based study was conducted to evaluate the potential toxic effects of TRX and EGF proteins, as safety assessments are necessary for the commercial use of seed-specific protein-expressing transgenic soybeans. To achieve this rationale, TRX and EGF proteins were mass purified from recombinant E. coli. The single-dose oral-toxicity tests of the TRX and EGF proteins were carried out in six-week old male and female Institute of Cancer Research (ICR) mice. The initial evaluation of the single-dose TRF and EGF treatments was based on monitoring the toxicity signatures and mortality rates among the mice, and the resultant mortality rates did not show any specific clinical symptoms related to the proteins. Furthermore, no significant differences were observed in the weights between the treatment and control groups of male and female ICR mice. After 14 days of treatment, no differences were observed in the autopsy reports between the various treatment and control groups. These results suggest that the minimum lethal dose of TRX and EGF proteins is higher than the allowed 2,000 mg·kg-1 limit.

Importance of PET/CT Scan Use in Planning Radiation Therapy for Lymphoma

  • Milana, Mitric-Askovic;Marko, Erak;Miroslav, Latinovic;Tihomir, Dugandzija
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권5호
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    • pp.2051-2054
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    • 2015
  • Background: Radiation therapy is a key part of the combined modality treatment for Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), which can achieve locoregional control of disease. The 3D-conformal radiation oncology can be extended-field (EFRT), involved-field (IFRT) and involved node (INRT). New techniques have resulted in a smaller radiation field and lower dose for critical organs such as lung heart and breast. Materials and Methods: In our research, we made a virtual simulation for one patient who was treated in four different radiotherapeutic techniques: mantle field (MFRT), EFRT, IFRT and INRT. After delineatiion we compared dose-volume histograms for each technique. The fusion of CT for planning radiotherapy with the initial PET/CT was made using Softver Xio 4.6 in the Focal program. The dose for all four techniques was 36Gy. Results: Our results support the use of PET/CT in radiation therapy planning. With IFRT and INRT, the burden on the organs at risk is less than with MFRT and EFRT. On the other hand, the dose distribution in the target volume is much better with the latter. Conclusions: The aim of modern radiotherapy of HL and NHL is to reduce the intensity of treatment and therefore PET/CT should be used to reduce and not increase the amount of tissue receiving radiation.

Gamma Knife Radiosurgery for Trigeminal Neuralgia : Review and Update

  • Lee, Seunghoon;Lee, Jung-Il
    • Journal of Korean Neurosurgical Society
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    • 제65권5호
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    • pp.633-639
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    • 2022
  • Accurate diagnosis of trigeminal neuralgia (TN) is the starting point for optimal treatment. Gamma knife radiosurgery (GKRS) is currently regarded as one of the first-line treatment options for medically refractory TN. GKRS is a less invasive treatment with a low risk of complications than other surgical procedures that provides a favorable pain control Barrow Neurological Institute (BNI) I-IIIb rate of >75% at short-term follow-up. Drawbacks of GKRS include the latency period before pain relief and higher recurrence rate compared with microvascular decompression. Therefore, repeat treatment is necessary if the initial GKRS was effective but followed by recurrence. The concept of dose rate and the biologically effective dose of radiation has been actively studied in radiation oncology and is also applied in GKRS for TN to achieve high safety and efficacy by prescribing the optimal dose. Recent progress in functional imaging, such as diffusion tensor imaging, enables us to understand the pathophysiology of TN and predict the clinical outcome after GKRS. Here, we review TN, GKRS, and recent updates, especially in the concepts of radiation dose, diffusion tensor imaging studies, and repeat treatment in GKRS for TN.

방사성옥소($^{131}I$) 치료 시 유효선량과 체질량지수의 상관관계 (Correlation of Effective Dose and BMI in Radioiodine($^{131}I$) Therapy)

  • 신규설;김건재;동경래;김현수
    • 대한방사선기술학회지:방사선기술과학
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    • 제31권1호
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    • pp.11-16
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    • 2008
  • 목적: 갑상선 암 환자에서 방사성옥소($^{131}I$) 치료 시 체질량지수와 초기 유효선량 값의 상관관계를 알아보고, 또한 갑상선치료 환자로부터 1 m 떨어진 옆 사람에게 전달되는 유효선량 값을 측정하여 환자의 격리가 언제까지 필요한지 알아보고자 한다. 재료 및 방법: 치료당일 오전에 금식을 하게 하여 입원실에서 신장과 체중을 측정하였다. 방사성옥소($^{131}I$) 150 mCi를 환자에게 투여하기 전에 핵의학과에서 병에 들어있는 I-131 capsule을 방사선량 측정기[ATOMLAB DOSE CALIBRATORS(Biodex Medical Systems)]로 측정하여 기록 하여둔다. 치료적 용량 150 mCi(${\pm}6\;mCi$)를 투여받은 환자는 격리된 입원실에서 투여 후 바로 1 m 거리에서 초기 유효선량을 G-M survey meter로 측정하고 다음날 아침에도 같은 방법으로 선량을 측정하여 법정인 허용선량이 되면 퇴원 처방을 내고 $4{\sim}5$시간 후에 퇴원을 한다. 자료 분석은 Med calc Version 9,2,1,0통계 프로그램 이용하여 분석하였다. 결과: 초기 유효선량 값과 체질량지수 상관관계를 분석한 결과 Correlation coefficient 값이 음의 값으로 체질량지수가 증가할수록 초기 유효선량 값은 감소함을 알 수 있었다. 또한 P=0.0004로 유의한 결과임을 알 수 있었다. 체질량지수에 따른 group간의 비교를 하기위해 One-way ANOVA분석한 결과 체지방지수가 증가할수록 초기 유효선량 값이 감소하는 것을 알 수 있었다. 또한 P=0.007로 유의한 결과임을 알 수 있었다. 결론: 체질량지수와 초기선량과의 관계는 밀접한 상관관계가 있었고, 53%의 환자가 NRC규정에서 권고하는 선량을 만족시켜 1박2일 동안 입원을 하였다. 따라서 체질량지수와 초기 유효선량과의 관계를 잘 이용하게 되면 병실 회전율에 도움이 되리라 사료된다.

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가토 기흉에서 본 $^{86}Rb$의 분포 ($^{86}Rb$ Distribution in the Lung of the Rabbit with Pneumothorax)

  • 허갑도
    • 대한핵의학회지
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    • 제6권1호
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    • pp.51-59
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    • 1972
  • $^{86}Rb$ uptake of some organs and tissues, ego both lungs, both renal cortices. small intestine, liver and skeletal muscle were studied in the control and the rabbit subjected to pneumothorax. $^{86}Rb$ in the form of chloride mixed with physiological saline was intravenously. injected. The doses were $100{\mu}c$ for a rabbit. The rabbits were sacrificed at intervals of 10, 20, 40, and 60 seconds after the injection of $^{86}Rb$, by the injection of saturated KCI solution. After sacrification, the organ and tissue sample were quickly removed. $^{86}Rb$ uptake in gm of the organs and tissues were measured. On the basis of uptake value, administered doses and body weight, % dose/gm tissues per 200 gm body weight was calculated. Followings were the results; 1. Pneumothorax resulted in a marked elevation in $^{86}Rb$ uptake value of collapsed lung and returned to normal level lately. 2. Contralateral lung of pnemothorax also showed marked elevation in $^{86}Rb$ uptake value and recovered to normal level. 3. Initial $^{86}Rb$ uptake value of liver, small intestine of the rabbit with pneumothorax showed some elevation as compared to control, but that of late stage were similar with control. 4. Local blood flow determination by means of $^{86}Rb$ uptake were inadequate in the collapsed lung of pneumothorax. 5. It was suggested that the mechanism for the initial elevation of $^{86}Rb$ uptake value in each organs and tissue were different from each other.

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Adverse Effect of Nonylphenol on the Reproductive System in F1 Male Mice: A Subchronic Low-Dose Exposure Model

  • Kim, Yong-Bin;Cheon, Yong-Pil;Lee, Sung-Ho
    • 한국발생생물학회지:발생과생식
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    • 제23권2호
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    • pp.93-99
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    • 2019
  • Nonylphenols (NPs) are widely used industrial materials, and are considered as potent endocrine disrupting chemical. Present study was undertaken to clarify the effect of subchronic low-dose NP exposure to F1 generation male mice. Mice were divided into 2 groups; (1) CON, control animals and (2) NP-50 ($50{\mu}g/L$), animals were treated with NP via drinking water. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 55 of F1 offsprings. Mice were sacrificed on PND 55 and the tissue weights were measured. The initial body weights (at PND 21) and terminal body weights (PND 55) of the NP-50 animals were significantly lower than those of control animals (p<0.05). NP exposure induced a significant increase in the absolute weight of the testes (p<0.05). Conversely, the NP exposure caused significant decrease in the absolute weights of the epididymis (p<0.01), prostate (p<0.05) and seminal vesicle (p<0.05). Histopathological studies revealed that NP-treated animals exerted decreased seminiferous tubule diameters, reduced luminal area, and lower number of germ cells. Also some sloughing morphologies in the tubules were observed. In the caudal epididymis, fewer mature sperms and swollen epithelial cells were found in the NP-treated group. Our results confirmed that the subchronic low-dose NP exposure altered some male parameters and induced histopathological abnormalities in testis and epididymis of F1 mice. Since the NP dose used in this study is close to the average human daily NP exposure, our results could provide practically meaningful understanding of adverse effect of EDC in human.

Low-dose intravenous ketamine versus intravenous ketorolac in pain control in patients with acute renal colic in an emergency setting: a double-blind randomized clinical trial

  • Sotoodehnia, Mehran;Farmahini-Farahani, Mozhgan;Safaie, Arash;Rasooli, Fatemeh;Baratloo, Alireza
    • The Korean Journal of Pain
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    • 제32권2호
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    • pp.97-104
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    • 2019
  • Background: This study was conducted to compare the effectiveness of low-dose ketamine versus ketorolac in pain control in patients with acute renal colic presenting to the emergency department (ED). Methods: This is a double-blind randomized clinical trial. The initial pain severity was assessed using the numerical rating scale (NRS). Then, ketamine or ketorolac was administered intravenously at a dose of 0.6 mg/kg and 30 mg respectively. The pain severity and adverse drug reactions were recorded 5, 15, 30, 60, and 120 min thereafter. Results: The data of 62 subjects in the ketamine group and 64 patients in the ketorolac group were analyzed. The mean age of the patients was $34.2{\pm}9.9$ and $37.9{\pm}10.6\;years$ in the ketamine and ketorolac group, respectively. There was no significant difference in the mean NRS scores at each time point, except for the 5 min, between the two groups. Despite a marked decrease in pain severity in the ketamine group from drug administration at the 5 min, a slight increase in pain was observed from the 5 min to the 15 min. The rate of adverse drug reactions, including dizziness (P = 0.001), agitation (P = 0.002), increased systolic blood pressure (> 140 mmHg), and diastolic blood pressure (> 90 mmHg) was higher in the ketamine group. Conclusions: Low dose ketamine is as effective as ketorolac in pain management in patients with renal colic presenting to the ED. However, it is associated with a higher rate of adverse drug reactions.