• Title/Summary/Keyword: High dose rate

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The Effect of Surfactant on Neutrophil Apoptosis in Lipopolysaccharide Induced Acute Lung Injury in Rat (기관내 내독소 투여로 유도한 백서의 급성 폐손상 모델에서 surfactant가 호중구의 아포토시스에 미치는 영향)

  • Yoo, Ji-Hoon;Lee, Byoung-Jun;Jeong, Do-Young;Lee, Sang-Hoon;Shin, Jong-Wook;Kim, Jae-Yeol;Park, In-Won;Choi, Byoung-Whui
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.4
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    • pp.409-419
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    • 2002
  • Background : The therapeutic effects of surfactant on acute lung injury derive not only from its recruiting action on collapsed alveoli but also from its anti-inflammatory effects. Pro-apoptotic action on alveolar neutrophils represents one of the important anti-inflammatory mechanisms of surfactant. In the present study, we evaluated the effects of sufactant on the apoptosis of human peripheral and rat alveolar neutrophils. Methods : In the (Ed- the article is not definitely needed but it helps to separate the two prepositions 'in') in vitro study, human neutrophils were collected from healthy volunteers. An equal number of neutrophils ($1{\times}10^6$) (Ed-confirm) was treated with LPS (10, 100, 1000ng/ml), surfactant (10, 100, $1000{\mu}g/ml$), or a combination of LPS (1000ng/ml) and surfactant (10, 100, $1000{\mu}g/ml$). After incubation for 24 hours, the apoptosis of neutrophils was evaluated by Annexin V method. In the in vivo study, induction of acute lung injury in SD rats by intra-tracheal instillation of LPS (5mg/kg) was followed by intra-tracheal administration of either surfactant (30mg/kg) or normal saline (5ml/kg). Tenty-four hours after LPS instillation, alveolar neutrophils were collected and the apoptotic rate was evaluated by Annexin V method. In addition, changes of the respiratory mechanics of rats (respiratory rate, tidal volume, and airway resistance) were evaluated with one chamber body plethysmography before, and 23 hours after, LPS instillation. Results : in the in vitro study, LPS treatment decreased the apoptosis of human peripheral blood neutrophils (control: $47.4{\pm}5.0%$, LPS 10ng/ml; $30.6{\pm}10.8%$, LPS 100ng/ml; $27.5{\pm}9.5%$, LPS 1000ng/ml; $24.4{\pm}7.7%$). The combination of low to moderate doses of surfactant with LPS promoted apoptosis (LPS 1000ng/ml + Surf $10{\mu}g/ml$; $36.6{\pm}11.3%$, LPS 1000ng/ml +Surf $100{\mu}g/ml$; $41.3{\pm}11.2%$). The high dose of surfactant ($1000{\mu}g/ml$) decreased apoptosis ($24.4{\pm}7.7%$) and augmented the anti-apoptotic effect of LPS (LPS 1000ng/ml + Surf $1000P{\mu}g/ml$; $19.8{\pm}5.4%$). In the in vivo study, the apoptotic rate of alveolar neutrophils of surfactant-treated rats was higher than that of normal saline-treated rats ($6.03{\pm}3.36%$ vs. $2.95{\pm}0.58%$). The airway resistance (represented by Penh) of surfactant-treated rats was lower than that of normal saline-treated rats at 23 hours after LPS injury ($2.64{\pm}0.69$ vs. $4.51{\pm}2.24$, p<0.05). Conclusion : Surfactant promotes the apoptosis of human peripheral blood and rat alveolar neutrophils. Pro-apoptotic action on neutrophils represents one of the important anti-inflammatory mechanisms of surfactant.

The Results and Prognostic Factors of Chemo-radiation Therapy in the Management of Small Cell Lung Cancer (항암화학요법과 방사선 치료를 시행한 소세포폐암 환자의 치료 성적 -생존율과 예후인자, 실패양상-)

  • Kim Eun-Seog;Choi Doo-Ho;Won Jong-Ho;Uh Soo-Taek;Hong Dae-Sik;Park Choon-Sik;Park Hee-Sook;Youm Wook
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.433-440
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    • 1998
  • Purpose : Although small ceil lung cancer (SCLC) has high response rate to chemotherapy and radiotherapy (RT), the prognosis is dismal. The authors evaluated survival and failure patterns according to the prognostic factors in SCLC patients who had thoracic radiation therapy with chemotherapy. Materials and Methods : One hundred and twenty nine patients with SCLC had received thoracic radiation therapy from August 1985 to December 1990. Seventy-seven accessible patients were evaluated retrospectively among 87 patients who completed RT. Median follow-up period was 14 months (2-87months). Results : The two years survival rate was 13$\%$ with a median survival time of 14 months. The two year survival rates of limited disease and extensive disease were 20$\%$ and 8$\%$, respectively, with median survival time of 14 months and 9 months, respectively. Twenty two patients (88$\%$) of limited disease showed complete response (CR) and 3 patients (12$\%$) did partial response (PR). The two year survival rates on CR and PR groups were 24$\%$ and 0$\%$, with median survival times of 14 months and 5 months. respectively (p=0.005). No patients with serum sodium were lower than 135 mmol/L survived 2years and their median survival time was 7 months (p=0.002). Patients whose alkaline phophatase lower than 130 IU/L showed 26$\%$ of 2 year survival rate and showed median survival time of 14 months and those with alkaline phosphatase higher than 130 IU/L showed no 2 year survival and median survival time of 5 the months, respectively (p=0.019). No statistical differences were found according to the age, sex, and performance status. Among the patients with extensive disease, two rear survivals according to the metastatic sites were 14$\%$, 0$\%$, and 7$\%$ in brain, liver, and other metastatic sites, respectively, with median survival time of 9 months, 9 months, and 8 months, respectively (p>0.05). Two year survivals on CR group and PR group were 15$\%$ and 4$\%$, respectively, with a median survival time of 11 months and 7 months, respectively (p=0.01). Conclusion : For SCLC, complete response after chemoradiotherapy was the most significant prognostic tactor. To achieve this goal. there should be further investigation about hyperfractionation, dose escalation, and compatible chemo-radiation schedule such as concurrent chemo-radiation and early radiation therapy with chemotherapy.

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Effect of $H_2O_2$ on Alveolar Epithelial Barrier Properties (폐상피세포 장벽에 대한 $H_2O_2$의 영향)

  • Suh, Duk-Joon;Cho, Se-Heon;Kang, Chang-Woon
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.3
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    • pp.236-249
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    • 1993
  • Background: Among the injurious agents to which the lung airspaces are constantly exposed are reactive species of oxygen. It has been widely believed that reactive oxygen species may be implicated in the etiology of lung injuries. In order to elucidated how this oxidant causes lung cell injury, we investigated the effects of exogenous $H_2O_2$ on alveolar epithelial barrier characteristics. Methods: Rat type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with HEPES-buffered Ringer solution. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against $H_2O_2$ injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ, an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results: These monolayers have a high transepithelial resistance (>2000 ohm-$cm^2$) and actively transport $Na^+$ from apical fluid. $H_2O_2$(0-100 mM) was then delivered to either apical or basolateral fluid. Resulting indicated that $H_2O_2$ decreased Isc and R gradually in dose-dependent manner. The effective concentration of apical $H_2O_2$ at which Isc (or R) was decreased by 50% at one hour ($ED_{50}$) was about 4 mM. However, basolateral $H_2O_2$ exposure led to $ED_{50}$ for Isc (and R) of about 0.04 mM. Inhibition of cellular catalase yielded $ED_{50}$ for Isc (and R) of about 0.4 mM when $H_2O_2$ was given apically, while $ED_{50}$ for basolateral exposure to $H_2O_2$ did not change in the presence of ATAZ. The rate of $H_2O_2$ consumption in apical and basolateral bathing fluids was the same, while cellualr catalase activity rose gradually with time in culture. Conclusion: Our data suggest that basolateral $H_2O_2$ may affect directly membrane component (e.g., $Na^+,\;K^+$-ATPase) located on the basolateral cell surface. Apical $H_2O_2$, on the other hand, may be largely degraded by catalase as it passes through the cells before reaching these membrane components. We conclude that alveolar epithelial barrier integrity as measured by Isc and R are compromised by $H_2O_2$ being relatively sensitive to basolateral (and insensitive to apical) $H_2O_2$.

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Effect of Pelvic Irradiation on the Bone Mineral Content of Lumbar Spine in Cervical Cancer (자궁경부암 환자에서 방사선 치료가 골무기물 함량에 미치는 영향)

  • Youn Seon Min;Choi Tae Jin;Koo Eun Sil;Kim Ok Bae;Lee Seung Moon;Suh Soo Jhi
    • Radiation Oncology Journal
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    • v.15 no.2
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    • pp.145-151
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    • 1997
  • Purpose : To evaluate the loss of bone mineral contents(BMC) in lumbar spine within the radiation field for cervical cancer treatment, BMC in the irradiated patient group was compared with that of a normal control group. Method and materials : Measurements of BMC in the trabecular bone in lumbar spines(L3-L5) were performed in the both patient and normal control groups. Investigators used dual-energy quantitative computerized tomography(DEQCT) using Photon energy of 120 and 80kVp, The numbers of Patient and control groups were 43 in each with age distribution of fifth to seventh decade of women. The numbers of control group were 22 in fifth, 10 in sixth and 11 in seventh decade, those of patient group were 14 in filth, 14 in sixth, and 15 in seventh decade of women. The radiation field was extended to L5 spine for Pelvic irrdiation with 45-54Gy of external radiation dose and 30Gy of high dose rate brachytherapy in cervical cancer, Results : The BMC is decreased as increasing age in both control and patient groups. BMC in lumbar spine of patient group was decreased by about $13\%\;to\;40\%$ maximally. The BMC of L3 and L4 a region that is out of a radiation field for the Patient group demonstrated $119.5\pm30.6,\;117.0\pm31.7\;for\;fifth,\;83.3\pm37.8,\;88.3\pm46.8\;for\;sixth\;and\;61.5\pm18.3,\;56.2\pm26.6mg/cc$ for seventh, Contrasted by the normal control group has shown $148.0\pm19.9,\;153.2\pm23.2\;for\;fifth,\;96.1\pm30.2,\;105.6\pm26.5\;for\;sixth\;and\;73.9\pm27.9,\;77.2\pm27.2mg/cc$ for seventh decade, respectively The BMG of patient group was decreased as near the radiation field, while the lower lumbar spine has shown more large amounts of BMC in the normal control group. In Particular, the BMC of L5 within the radiation field was significantly decresed to $33\%,\;31\%,\;40\%$ compared with the control group of the fifth, sixth and seventh decades, respectively. Conclusion : The pelvic irradiation in cervical cancer has much effected on the loss of bone mineral content of lumbar spine within the radiation field, as the lower lumbar spine has shown a smaller BMC in Patient group with Pelvic irradiation in contrast to that of the normal control groups.

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The Palliative Radiation Therapy in Malignant Extra-Hepatic Biliary Obstruction (간외 폐쇄성 황달 환자에서 고식적 방사선치료의 결과)

  • Kay Chul-Seoung;Jang Hong-Suk;Kim Sung-hwan;Ryu Mi-Ryeong;Kim Yeon-Shil;Chung Su-Mi;Yoon Sei-Chul
    • Radiation Oncology Journal
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    • v.17 no.3
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    • pp.209-216
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    • 1999
  • Purpose : To evaluate the effectiveness of external radiation therapy and the prognostic factors, we retrospectively analyzed therapeutic results of malignant extrahepatic biliary obstruction (EHBO). Methods and Materials : We analyzed the results of the external radiation therapy in 59 patients of inoperable malignant EHBO who had been treated with more than 10 Gy of external radiation therapy from April 1984 to December 1990. There were 21 stomach cancer ($35.6\%$), 12 pancreas cancer ($20.3\%$), 15 extrahepatic biliary cancer ($18.0\%$) and 11 another cancer ($18.0\%$). Their pathologies were confirmed in 31 patients ($52.5\%$). They divided into 27 adenocarcinoma and 4 nonadenocarcinoma. Their chief complaints were jaundice in 47 patients ($79.7\%$) and abdominal pain in 15 patients ($49.2\%$). Twelve patients had slightly increased bilirubin level in liver function test without jaundice. We treated twenty four patients ($40.6\%$) with percutaneous transhepatic biliary drainage (PTBD) and 32 patients ($54\%$) with systemic chemotherapy (CT). We performed external radiation therapy (ERT) upto $10.8\~55.8$ Gy (median 37.8 Gy) with palliative aim. Results : Overall median survival duration was $7.80\pm1.15$ months. The response rates of jaundice were $81.8\%$ in PTBO group and $66.7\%$ in non-PTBD group without statistical significance. The improving rate of jaundice was not significantly different in decreased ratio of total bilirubin level. But abdominal pain was more decreased in CT group than non-CT group (p<0.05). The significant prognostic factors were high performance status (Karnofski Performance Status >70), total radiation dose more than 35 Gy and good response of pain after therapy. There were increased in bacterial cholagitis in PTBD group and gastrointestinal complications in CT group. Conclusion : External radiotheapy could improve jaundice and abdominal pain in malignant EHBO patients, Overall survival duration was prolonged in patients with higher performance status and patients who had been treated with more than 35 Gy of total radiation dose. In the future, we expect not only better palliative role but also the prolongation of survival of using the ERT combined with other treatment method. But to achieve certain conclusion, we need luther study consisted with many kinds of treatment methods including new technologies in RT.

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Study on the changes of sulfamethnzine residues in serum and practical organs of rats orally administrated with sulfamethnzine sodium (Rat에 sulfamethazine sodium 경구투여 후 혈청 및 실질장기내 sulfamethazine의 잔류량 추이에 관한 연구)

  • 도재철;이영미;조민희;신상희;박희주;송희종;정종식
    • Korean Journal of Veterinary Service
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    • v.23 no.4
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    • pp.321-333
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    • 2000
  • In order to know the depletive changes of sulfamethazine residues in senlm and practical organs of rats orally administered with sulfamethazine sodium(SMS), the concentration of sulfamethazine was measured in serum and tissue(kidney, liver, spleen, testis, and skeletal muscle) of rats with using high performance liquid chromatography(HPLC). SMS was orally administrated to sprague-dawley male rats(body weight, 200~300g) with using sonde at the rate of 20mg/100g body weight(recommended therapeutic dose) on once a day for 3 days. There were investigated the depletive changes of the sulfamethazine in serum, kidney, liver, spleen, testis and skeletal muscle of rat at the time 8 hours, 1st, 2nd, 3rd, 4th, 5th and 6th day after administration SMS, respectively. The results obtained were summarized as follows; 1. After oral administration of the SMS, the mean concentrations of sulfamethazine in serum according to the time lapsed were showed 215.53$\pm$42.99ppm at the 8 hours after withdrawal of medicated sulfamethazine. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in serum were significantly (p<.05) decreased 25.87$\pm$5.18ppm at 1st day, 2.30$\pm$0.61ppm at 3rd day and 0.11$\pm$0.02ppm at 6th day respectively. 2. The mean concentrations of sulfamethazine in kidney, liver, spleen, muscle and testis according to the time lapsed after administration SMS were showed 83.82$\pm$12.16, 81.77$\pm$12.88, 36.96$\pm$5.35, 35.96$\pm$TEX>$\pm$1.39 and 27.89$\pm$1.92 ppm at the 8 hours, respectively. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in the each of samples were significantly(p<.05) decreased such as 7.15$\pm$0.26, 5.62$\pm$0.72, 2.43$\pm$0.29, 1.99$\pm$0.14 and 3.11$\pm$0.48 ppm at 1st day, 0.52$\pm$0.04, 1.32$\pm$0.22, 0.13$\pm$0.03, 0.15$\pm$0.06 and 0.26$\pm$0.11ppm at 3rd day, and 0.03$\pm$0.01, 0.11$\pm$0.03, 0.02$\pm$0.01, 0.009$\pm$0.001 and 0.02$\pm$0.01 ppm at 6th day, respectively. 3. After oral administration of the SMS to rats, the residual concentrations of sulfamethazine in skeletal muscle were significantly (p<.05) decreased 35.96$\pm$1.39 to 0.009$\pm$$\pm$0.001 ppm between 8 hours and 6th day, respectively From the 4th day, the residual concentrations of sulfamethazine were showed 0.10$\pm$0.04 ppm below 0.1 ppm at the permitted limit concentration of muscle in Korea. In conclusion, this study could be suggested the relationship between administrated period, doses of sulfonamides and residual aspects of serum and practical organs, and the importance of observing ceasing period of antibiotic drugs before forwarding livestocks to slaughter.

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Effect of ω3-Fatty Acid Desaturase Gene Expression on Invasion and Tumorigenicity in Human Tongue Squamous Cell Carcinoma Cells (인체 혀의 편평세포암 세포에서 ω3-fatty acid desaturase 유전자 발현이 침윤 및 종양형성에 미치는 영향)

  • Hong, Tae-Hwa;Shin, Soyeon;Han, Seung-Hyeon;Hwang, Byung-Doo;Lim, Kyu
    • Journal of Life Science
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    • v.28 no.8
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    • pp.945-954
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    • 2018
  • Omega-3 polyunsaturated fatty acids (${\omega}3$-fatty acid) have been found to possess anticancer properties in a variety of cancer cell lines and animal models, but their effects in human tongue squamous cell carcinomas (SCCs) remain unclear. This study was designed to examine the effect of ${\omega}3$-fatty acid desaturase (fat-1) gene expression on invasion and tumorigenicity in human tongue SCC cells and the molecular mechanism of its action. Docosahexaenoic acid (DHA) treatment inhibited in vitro invasion in a dose-dependent manner. In zymography, matrix metalloproteinase-9 (MMP-9) and Matrix metallopeptidase-2 (MMP-2) activities were reduced, and MMP-9 and MMP-2 promoter activities were inhibited by the DHA treatment. In addition, cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) promoter reporter activities were inhibited in SCC-4 and SCC-9 cells after the DHA treatment. To investigate the effect of a high level of endogenous ${\omega}3$ fatty acids, a stable SCC-9 cell line expressing the ${\omega}3$-desaturase gene (fSCC-9sc) was generated. The growth rate and colony-forming capacity of fSCC-9sc were remarkably decreased as compared with those of fSCC-9cc. Likewise, the tumor size and volume of fSCC-9sc implanted into nude mice were significantly inhibited, with increases in the cell death index. Furthermore, a transwell chamber invasion assay showed a reduction in cell invasion of the fSCC-9sc lines when compared with that of the fSCC-9cc line. These findings suggested that fat-1 gene expression inhibited tumorigenicity, as well as invasion in human tongue SCC cells. Thus, utilization of ${\omega}3$ fatty acids may represent a promising therapeutic approach for chemoprevention and the treatment of human tongue SCCs.

Effects of $^{60}Co-gamma$ Radiation on Ricebran Oil (미강유에 대한 코발트 60-감마선의 영향에 관한 연구)

  • Han, Deok-Bong;Suck, Han-Gyun;Yoo, Young-Jin
    • Korean Journal of Food Science and Technology
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    • v.5 no.2
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    • pp.129-135
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    • 1973
  • The accumulation of peroxides, acid values, and carbonyl values during irradiation and post-irradiation storage of the ricebran oil has been studied. The rice bran oils were irradiated two doses of 2 and 7 megarads (300 rads/sec) at $23^{\circ}C$ atmospheric circumstance. The acid values, peroxide values and carbonyl values were measured at regular intervals of one week during the storage at $5^{\circ}C$ and $25^{\circ}C$. 1) During the storage, the acid values of the irradiated rice bran oils increased or decreased insignificantly regardless of the addition of antioxidants and storage temperature. 2) The peroxide values were not increased continuously but increased zigzag. The result was indicated that the composition and decomposition of peroxides occurred continuously throughout the storage. 3) As the peroxide values increased, carbonyl values decreased and changed quite differently, but, especially in 7th week, they were constant or insignificant. 4) Dibutylhydroxytoluene is more effective than caffeic acid in retarding the formation of peroxides during irradiation of rice bran oils and post-irradiation storage. The effect of antioxidant is more efficient at 2 megarads than at 7 megarads irradiation. When we store the rice bran oil, the addition of antioxidants of post-irradiation is more desirable than that of preirradiation. 5) In spite of changing conditions such as storage temperature and addition of antioxidants, the peroxide values of rice bran oils irradiated at 2 megarads were always greater than those at 7 megarads during the storage. Peroxide values of samples at high temperature $(25^{\circ}C)$ storage increased as twice as those of low temperature $(5^{\circ}C)$ storage samples. At low temperature, peroxide values in the first week increased twice during the period of 8th weeks storage, but those did from three to four times at higher temperature in the same period Therefore, the low temperature storage is recommandable too.

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Comparing Concurrent Chemoradiotherapy to Chemotherapy Alone for Locally Advanced Unresectable Pancreatic Cancer (절제 불가능한 췌장암의 동시 항암화학 방사선 요법과 항암화학 단독 요법의 비교)

  • Park, Jeong-Hoon;Kim, Woo-Chul;Kim, Hun-Jung;Gwak, Hee-Keun
    • Radiation Oncology Journal
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    • v.27 no.2
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    • pp.64-70
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    • 2009
  • Purpose: Concurrent chemoradiotherapy (CCRT) is the standard treatment for locally advanced unresectable pancreatic cancer. However, the introduction of gemcitabine and the recognition of a benefit in patients with advanced disease stimulated the design of trials that compare chemotherapy alone to concurrent chemoradiation. Therefore, we evaluated role of CCRT for locally advanced unresectable pancreatic cancer. Materials and Methods: We carried out a retrospective analysis of treatment results for patients with locally advanced unresectable pancreatic cancer between January 2000 and January 2008. The radiation was delivered to the primary tumor and regional lymph nodes with a 1~2 cm margin at a total dose of 36.0~59.4 Gy (median: 54 Gy). The chemotherapeutic agent delivered with the radiation was 5-FU (500 mg/$m^2$). The patients who underwent chemotherapy alone received gemcitabine (1,000 mg/$m^2$) alone or gemcitabine with 5-FU. The follow-up period ranged from 2 to 38 months. The survival and prognostic factors were analyzed using Kaplan-Meier method and log-rank test, respectively. Results: Thirty-four patients received concurrent chemoradiotherapy, whereas 21 patients received chemotherapy alone. The median survival time was 12 months for CCRT patients, compared to 11 months for chemotherapy alone patients (p=0.453). The median progression-free survival was 8 months for CCRT patients, compared to 5 months for chemotherapy alone patients (p=0.242). The overall response included 9 partial responses for CCRT and 1 partial response for chemotherapy alone. In total, 26% of patients from the CCRT group experienced grade 3~4 bowel toxicity. In contract, no grade 3~4 bowel toxicity was observed in the chemotherapy alone group. The significant prognostic factors of overall survival were lymph node status, high CA19-9, and tumor location. Conclusion: The response rate and progression-free survival were more favorable in the CCRT group, when compared with the chemotherapy alone group. Therefore, radiation therapy seems to be an effective tool for local tumor control.

A study on the accuracy of source position in HDR brachytherapy according to the curvature of Universal applicator transfer tube and applicator type (원격 후 장전치료기를 사용한 고선량률 근접치료시 기구의 형태와 선원 전달 도관의 곡률 변화에 따른 선원위치 정확성에 관한 고찰)

  • Shin, Hyeon Kyung;Lee, Sang Kyoo;Kim, Joo Ho;Cho, Jeong Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.2
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    • pp.123-129
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    • 2015
  • Purpose : The goal of this study was to verify and analyze the source position according to the curvature of the universal applicator and 4 different angle applicators when using RALS(Remote After Loading System). Materials and Methods : An interval of 1 cm and 15 second dwell times in each source position were applied for plan. To verify the accuracy of source position, we narrowed the distance between MultiSource container and GAFCHROMIC$^{(R)}$ EBT3 film by 5 cm, 10 cm, 20 cm so that the universal applicator transfer tube had some curvature. Also 4 applicators(Intrauterine tube: $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, Ovoid tube: $65^{\circ}$) were used in the same condition. The differences between desired and actual source position were measured by using Image J. Results : In case of using 4 different angles of applicator with the straight universal applicator transfer tube, the average error was the lowest for $0^{\circ}$ applicator, greatest for $65^{\circ}$ applicator. However, All average errors were within ${\pm}2mm$ recommended in TG-56. When MultiSource container was moved 5 cm, 10 cm, 20 cm towards the EBT3 film, the average errors were beyond ${\pm}2mm$. The first dwell position was relatively located in accuracy, while the second and third dwells were displaced by an increasing magnitude with increasing curvature of the transfer tube. Furthermore, with increasing the angle of applicators, the error of all other dwell positioning was increased. Conclusion : The results of this study showed that both the curvature of universal applicator transfer tube and the angle of applicators affect the source dwell position. It is recommended that using straight universal applicator transfer tubes is followed in all cases, in order to avoid deviations in the delivered source dwell position. Also, It is advisable to verify the actual dwell position, using video camera quality control tool prior to all treatments.

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