• Title/Summary/Keyword: 방사선학적 변화

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방사선 방호의 기반 : 무엇이 변하는가?

  • 이재기
    • Nuclear industry
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    • v.25 no.10 s.272
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    • pp.34-53
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    • 2005
  • 방사선 방호는 역동적이다. 위로는 방호의 개념과 틀에서부터 아래로는 사용하는 물리량과 수치 기준에 이르기까지 무엇 하나 불변인 것이 없어 보인다. 이와 같은 변화는 방사선의 작용과 생물보건학적 영향에 대한 우리 과학적 지식의 견고도도 관계되지만 방사선 방호가 본질적으로 과학의 문제만이 아니라 사회의 역동성과 연계되어 있기 때문이다. 방사선 위해도와 방호 체계에 상당한 변화가 있어 논

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The Effect of Pentoxifylline on Radiation-Induced Cardiac Injury in ICR Mice (방사선조사후 발생한 심장손상에서 Pentoxifylline 이 미치는 효과)

  • Suh Hyun Suk;Yang Kwang Mo;Kang Seung Hee;Kang Yun Kyung
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.281-290
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    • 1996
  • Purpose : Chest irradiation leads to a significant cardiac injury in a number of patients. To prevent, or to reduce the risk of radiation-induced cardiac injury, pentoxifylline(PTX), a haemorrheologic agent that improves the blood flow through small blood capillaries has been employed. Materials and Methods : One hundred and eighty ICR mice were divided into three study groups: control, radiation alone, and radiation-pentoxifylline. Each group was subdivided into 12 subgroups: 1 3, 6 and 10 days and 2, 3, 4, 6, 8, 12, 16 and 20 weeks by observation Period after irradiation. The total 15Gy of radiation was delivered in a single fraction through anterior mediastinal port. Pentoxifylline was injected subcutaneously daily 50mg/kg to the back of the mice from the first day of irradiation throughout the observation period. The mice of each group after a certain observation period were sacrificed and sectioned for histopathologic examination of the heart. Result : The findings of acute radiation-induced carditis i.e., heterophilic infiltration and vacuolization and ballooning of endothelial cells were observed upto 6 weeks and reduced sharply afterwards. The late radiation effects including pericarditis with mononuclear cell infiltration, pericardial fibrosis, endothelial cell changes, myocardial degeneration and fibrosis present from 4 weeks onwards after irradiation but with various degree of severity. The overall process of pathologic changes of radiation-pentoxifylline group was similar to those of radiation alone group but the duration of acute stage was relatively short and the severity of late cardiac toxicity was much lesser compared with those of radiation alone group. Conclusion : Pentoxifylline can effectively reduce the late radiation-induced cardiac injury and reslve the acute effects relatively rapidly.

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Gamma-ray-induced skin injury in the mini-pig: Effects of irradiation exposure on cyclooxygenase-2 expression in the skin (감마선조사에 의한 돼지 피부장애에 cyclooxygenase-2의 발현변화)

  • Kim, Joong Sun;Park, Sunhoo;Jang, Won Seok;Lee, Sun Joo;Lee, Seung Sook
    • Journal of Radiation Protection and Research
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    • v.40 no.1
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    • pp.65-72
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    • 2015
  • The basic concepts of radiation-induced skin damage have been established, the biological mechanism has not been studied. In this study, we have examined the effects of gamma rays on skin injury and cyclooxygenase(COX)-2 expression. Gamma irradiation induced clinicopathological changes in a dose- and time-dependent manner in mini-pig skin. The histological changes were consistent with the changes in gross appearance at 12 weeks after irradiation. After three days' irradiation, apoptotic cells in the basal layer were found more frequently in irradiated skin than in normal skin, with the magnitude of the effect being dose-dependent. The thickness of the epidermis transiently increased 3 days after irradiation, and then gradually decreased, although changes in the epithelial thickness of the irradiated field were not observed with irradiation doses over 50 Gy. In the epithelium, there was an initial degenerative phase, during which the rate of basal cell depletion was dependent on the radiation dose (20-70 Gy). One week after irradiation, COX-2 expression was mostly limited to the basal cell layer and was scattered across these cells. High COX-2 expression was detected throughout the full depth of the skin after irradiation. The COX-2 protein is upregulated after irradiation in mini-pig skin. These histological changes associated with radiation exposure dose cause the increased COX-2 expression in a dose-dependent fashion.

The Preliminarily Result of Radiologic Disappearance of the Calcific Material on One Time Ultrasonographic Assisted Needling (견관절의 석회화 건염에서 초음파 유도하 1회 주사요법에 의한 방사선학적 조기 소멸 정도에 대한 예비보고)

  • Yoo, Jae-Chul;Shon, Min-Soo;Koh, Kyoung-Hwan;Lim, Tae-Kang;Lee, Yeong-Seok
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.5 no.1
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    • pp.1-8
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    • 2012
  • Purpose: The purpose of this study is to report the preliminarily result of the radiologic disappearance of the calcific material, regardless of the size, type or location, on one-time ultrasonographic (US) assisted needling for calcific tendinitis of the shoulder. Materials and Methods: From March to August 2011, 46 patients (47 shoulders) with symptomatic calcific tendinitis were treated by one-time US assisted needling. Initially, a diagnostic US was performed with patient to determine the locations, numbers and sizes of calcific deposits. After 1% lidocaine local anesthesia, the calcific material was punctured with an 18-gauge needle under US monitoring. If no calcific material was aspirated after 2 or 3 additional attempts, the deposits was performed multiple puncture to achieve decompression. And then all patients were performed subacromial corticosteroid injection. All patients were followed up 4 weeks after procedure. To assess the radiologic disappearance after one-time US assisted needling, simple radiographs of the treated shoulder were performed and size, dense, and morphology of the calcific deposits were compared with those in baseline radiographs. For clinical evaluations, visual analogue scale for pain and function (PVAS and FVAS), and American Shoulder and Elbow Surgeons (ASES) score were assessed. Results: There were 11 male and 35 female patients with the mean age of 53.8 years (28-71). The morphology of the calcific deposits were 31 type A and 16 type B by French Arthroscopic Society classification and mean size was $2.9{\pm}6.7$ mm before the procedure. At 4 weeks after the index procedure, the radiographic unchanged group was included in 10 cases and changed group was 37 cases. No intergroup difference for the clinical results after the procedure was evident, but group FAS classification before the procedure was significantly different (p=0.011). Conclusion: At 4 weeks after one-time US assisted needling for calcific tendinitis of the shoulder, the radiographic size- or dense-changed cases were showed in 79%, regardless of the size, type or location of the calcific material. But the radiographic nearly or complete disappearance were showed in only 21%.

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COMPARATIVE STUDY ON THE CLINICAL AND RADIOGRAPHIC FINDINGS OF TEMPOROMANDIBULAR JOINT DYSFUNCTION PATIENTS (악관절 기능장애 환자의 임상적 방사선학적 소견에 관한 비교 연구)

  • Koh Kang;Ahn Hyung-Kyu
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.21 no.1
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    • pp.33-44
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    • 1991
  • 악관절 기능장애 환자 118명을 대상으로 하여 임상적으로 악관절 잡음, 개구량, 동통 및 병력을 조사하고 골변화 양상 및 악관절내에서의 과두위치 등을 방사선학적으로 관찰하였으며, 조영술식을 이용하여 악관절내의 원판 위치 및 천공등을 관찰하여 이들 조사결과를 비교 검토한 결과 다음과 같은 결론을 얻었다 1. 악관절 기능장애 환자에서 악관절부위의 골변화는 환자의 병력과 밀접한 관계가 있었다. 2. 최대 개구시 40㎜미만을 개구하는 환자에서 더욱 심한 골변화를 보였다. 3. 악관절 기능장애 환자의 교합상태에서 과두가 악관절강의 후방에 위치한 경우 개구시 더욱 쉽게 과두가 관절융기 전방으로 이동하였으며, 교합시 과두가 전방에 위치한 경우 후방에 위치한 경우보다 더욱 심한 골변화양상을 보였다. 4. 교합시 관절간격의 감소는 과두의 악관절내 어떠한 위치보다 병변이 진행된 상태였다. 5. 5. 비환원성 내장증 환자의 특징적 증상은 clicking후 개구장애를 나타내었으며 비환원성 내장증을 환원성 내장증보다 더욱 진행된 상태였다

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Effects of Low-Dose Fractionated Total Body Irradiation on Murine Immune System (마우스에서 전신 저선량 분할 방사선 조사에 의한 면역학적 변화 평가)

  • Kim, Mi-Hyoung;Rhu, Sang-Young;Lim, Dae-Seog;Song, Jie-Young
    • Journal of Radiation Protection and Research
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    • v.39 no.3
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    • pp.134-141
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    • 2014
  • Along with the wide use of radiotherapy in cancer treatment, there is growing interest in beneficial effect of low-dose irradiation (LDI) in cancer therapy. Therefore, we investigate how LDI affects immune responses in mice model. Total body irradiation (TBI) on C57BL/6 mice was given at low-dose rate of $1mGy{\cdot}min^{-1}$ using $^{137}Cs$ source at three times for consecutive three days. Hematological examination, total cell numbers of spleen, populations and characteristics of splenocytes were determined. Total numbers of RBC or platelet in irradiated mice showed no significant changes. WBC counts were decreased in a dose-dependent manner 2 days after TBI, however, these differences are gradually waned until 28 days. Dose-dependent decrease in the number of splenocytes of TBI mice at day 2 was also improved as time progressed. While the level of Foxp3 mRNA was decreased, the frequency of $CD4^+$ T cells and $CD69^+$ cells in spleen was increased at day 2 and 14. Fractionated low-dose TBI on mice exhibited normal body weight with no distinguishable behavior during whole experimental periods. These results suggest that some parameters of immune system could be altered and evaluated by fractionated low-dose TBI and be used to broaden boundary of low dose radiation research.

Radiation-Induced Proctitis in Rat and Role of Nitric Oxide (백서모델에서 방사선 직장염 유발인자로서의 Nitric oxide의 역할)

  • Chun Mison;Kang Seunghee;Jin Yoon-Mi;Oh Young-Taek;Kil Hoon-Jong;Oh Tae-Young;Ahn Byoung-Ok
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.265-274
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    • 2001
  • Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.

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A Case Report : TMJ Osteoarthritis in a Patient with Renal Osteodystrophy (턱관절의 골관절염을 동반한 신성골이영양증 환자 증례보고)

  • Lee, Gi-Ho
    • Journal of Oral Medicine and Pain
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    • v.38 no.3
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    • pp.247-253
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    • 2013
  • Renal osteodystrophy(RO) is characterized by skeletal changes in patients with renal disease and developed as a result of alterations in the metabolism of calcium, phosphate and secondary hyperparathyroidism. Bony changes in the craniofacial region include decreased bone density, radiolucent lesions(brown tumors), depletion of cortical bone and loss of lamina dura, but such changes rarely occur in the temporomandibular joint(TMJ). We report an uncommon case of bony changes and pain of both TMJs in a patient with RO. A 41-year-old man with RO came to our clinic due to TMJ pain and sounds. Occlusal change was also reported. Radiographs revealed degenerative changes of the both condyles. The patient had medical history of renal cancer therapy and hemodialysis. The patient was diagnosed with TMJ arthritis of RO and referred for systemic management through medication of calcium and vitamin D and parathyroidectomy. At 15-month follow-up, most of TMD symptoms disappeared and second radiographs revealed that bone density and cortical thickness of the mandible increased and the skeletal outline of the both condyles became relatively clear. As bony changes may begin in the early stage of the renal disease, dentists should be alert to detect the sign of the disease. In addition, it is important to differentiate TMJ arthritis of systemic cause because the treatment protocol is quite different.