Involute Construction 을 위한 복합재료 로켓 노즐의 Pattern 설계

이형식,예병한,정발 ( Hyung Sik Lee,Byung Hahn Yeh,Bal Jung ) 한국복합재료학회 1991 Composites research Vol.4 No.2

The Heterogeneity of T2NO Glottic Carcinoma Treated by Irradiation

이형식,문성록,안기정,정은지,서창옥,김귀언,노준규,Lee Hyung Sik,Moon Sun Rock,Ahn Ki Jung,Chung Eun Ji,Suh Chang Ok,Kim Gwi Eon,Loh John J K The Korean Society for Radiation Oncology 1990 Radiation Oncology Journal Vol.8 No.2

1978년 1월부터 1987년 12월 사이에 연세대학병원 치료방사선과에서 근치적 방사선치료를 받았던 44예의 T2NOMO 병기의 성문암 환자중 후향적 분석이 가능하였던 42예의 환자의 최소 추적기간은 3년 이었으며, 5년 추적조사 기간은 $81\%$에서 가능하였다. 전체 환자(42예)의 5년 생존율 및 무병생존율은 각각 $63.1\%$ 및 $53.3\%$이었다. 5년 무병 생존율을 기초로한 성문의 운동성 장애와 성문암의 국소 침윤정도에 따른 예후인자의 분석에 있어서 성문의 운동성이 정상이고 성문 하부로의 침윤이 존재하지 않은 14예의 환자의 5년 무병생존율은 $83.1\%$로 방사선 치료만으로도 성문의 운동성 장애가 있거나 성문 하부 침윤이 있었던 경우에 비하여 월등히 높은 치료 성적을 나타내어 T2NOMO 병기 내에도 방사선 치료에 다양한 반응을 보이는 아군 (subgroup) 이 존재함을 알 수 있었고 아울러 치료 실패 양상, 선량-반응 관계, 치료 실패환자의 수술요법 등에 관한 분석을 하여 향후 치료의 지침으로 삼고자하였다. During a ten-year period from 1978 through 1987, 44 patients with T2NOMO glottic cancer were treated with radical radiation therapy at the Yonsei University Medical Center. Forty-two patients had a minimum follow-up of 3 years, and $81\%$ had at least five years of follow-up. Patients were staged according to the AJCC system. Forty-two patients have been analyzed in detail with respect to two variables: the status of vocal cord mobility and the degree of local extension of the disease. Five-year local recurrence free survival rates were as follows: All 42 patients, $53.3\%$ patients with normal vocal cord mobility (n =18), $69.1\%$ versus patients with impaired vocal cord mobility (n=24), $43.4\%$(p<0.05); patients with subglottic extension (n=15), $36.7$ versus patients without subglottic extension (n=29), $61.9\%$ (p<0.05). The most favorable Prognostic group included the patients with normal mobility without subglottic extension (n=14), $83.1\%$. On the basis of this analysis, we confirmed the presence of heterogeneity in T2NOMO glottic cancer This study indicates that further randomized controlled trials are warranted to evaluate.

Interstitial Hyperthermia by Radiofrequency Needle Electrode System : Phantom and Canine Brain Studies

이형식,추성실,성진실,서창옥,김귀언,노준규,김영수,김선호,정상섭,한은경,김태승,Lee, Hyung-Sik,Chu, Sung-Sil,Sung, Jin-Sil,Suh, Chang-Ok,Kim, Gwi-Eon,Loh-John-Juhn-Kyu,Kim, Young-Soo,Kim, Sun-Ho,Chung, Song-Sup,Han, Eun-Kyung,Kim, Tae-S The Korean Society for Radiation Oncology 1991 Radiation Oncology Journal Vol.9 No.2

8MHz 라디오파를 이용한 자입식 온열치료를 위한 기초실험의 일환으로 조직등가물을 이용하여 다양한 needle electrode의 배열을 통한 적정 온도분포를 규명하고자 하였고, 직접 개의 뇌실질에 자입 온열요법을 시도하여 이에 따른 조직 병리학적 소견을 관찰하고자 하였다. 조직등가물 실침에서 저자들은 needle electrode 1 cm 간격의 정방형 배치에서 횡단면상 $90\%$ relative SAR 분포가 약 1.25 cm 반경의 균일한 원형으로 관찰됨을 알 수 있었고 종단면상 needle electrode의 길이에 따라 균일한 온도분포가 이루어짐을 관찰할 수 있었다. 정상 개의 뇌실질에 자입하여 직접 정방형의 중심을 $43^{\circ}C$로 유지하며 50분간 온열요법을 시행한 후 관찰한 조직 병리학적 소견은 liquefactive necrosis, pyknosis of neuronal element 및 Polymorphonuclear leukocytes들이 회백질에서 급성기에 관찰 되었고 liquefactive necrosis 주위에 lipid-laden macrophage들이 관찰됨이 공통적인 특징 이었으며 후기 변화로 괴사조직 주위로 신경교세포의 증식이 관찰되었다. An interstitial radiofrequency needle electrode system was constructed for interstitial heating of brain tissue. Radiofrequency electrodes with Thermotron RF 8 were tested in an agar phantom and in a normal canine brain to determine how variations in physical factors affected temperature distributions. Temperature distributions were checked after heating with 1 mm diameter needle electrode implants on the corners of 1 and 2 cm squares in a phantom and plot isotherms for various electrodes arrangement. We observed that the 1 cm square array would heat a volume with a 1.25 cm radius circular field cross section to therapeutic temperatures ($90\%$ relative SAR using Tm) and the 2 cm square array with a 1.75 cm radius rectangular field with central inhomogeneity. With 2 cm long electrode implants, we observed that the 1 cm square array would heat a 3 cm long sagittal section to therapeutic temperature ($90\%$ relative SAR using Tm). We found that radiofrequency electrodes could be selected to match the length of the heating area without affecting its performance. The histopathological changes associated with RF heating of normal canine brains have been correlated with thermal distributions. RF needle electrode heating was applied for 50min to generate tissue temperatures of $43^{\circ}C$. We obtained a quarter of the heated tissue material immediately after heating and sacrificed at intervals from $7\sim30$days. The acute stage (immediately after heating) was demonstrated by liquefactive necrosis, pyknosis of neuronal element in the gray matter and by some polymer-phonuclear leukocytes infiltration. The appearance of lipid-laden macrophages surrounding the area of liquefaction necrosis was demonstrated in all three sacrificed dogs. Mild gliosis occurring around the necrosis was demonstrated in the last sacrificed (Days 30) canine brain.

Micronucleus Test of PolycanTM, β-Glucan Originatedfrom Aureobasidium, in Bone Marrow Cells of Male ICR Mice

이형식,Hyung-Rae Cho,Kun-Ju Yang,Seung-Bae Moon,Bok-Ryeon Park,Hyun-Dong Shin,Hee-Jeong Jang,Lin-Su Kim,구세광 한국독성학회 2008 Toxicological Research Vol.24 No.1

In this research the genotoxic effect of PolycanTM β-glucans originated from Aureobasidium pullulans SM-2001, was evaluated using the mouse micronucleus test. PolycanTM was administered once a day for 2 days by oral gavage to male ICR mice at doses of 1000, 500 and 250 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control group. The appearance of a micronucleus is used as an index for genotoxic potential. The results obtained indicated that Polycan TM shows no genotoxicity effect up to 1000 mg/kg dosing levels. In addition, it is also considered that there were no problems from cytotoxicity of PolycanTM tested in this study because the polychromatic erythrocyte ratio was detected as > 0.47 in all tested groups.

피로 다시 쓴 흑인 여성의 역사 : 수잔-로리 팍스의 『붉은 글씨 희곡』 Suzan-Lori Parks`s Red Letter Plays

이형식 ( Hyung Shik Lee ) 한국영어영문학회 2008 영어 영문학 Vol.54 No.1

공동현상을 수반하는 볼 밸브 내 유동장 해석

이형식(Hyung Sik Lee),도기정(Gi Jung Do),이상호(Sang Ho Lee) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11

Numerical analysis has been performed to investigate water flow through a ball type valve subject to possible cavitation effect. At the inlet, uniform velocity of 5.5 ㎧ was applied and static pressure of 55,000 ㎩ was set at the outlet. Simulation results were compared for two rotation angles of the ball under the same boundary conditions. It was found that for the ball rotation angle of 30°, there was little cavitation over the flow field, whereas for the angle of 40° case, noticeable cavitation zone was spotted in the rear region of the pipe. For 40° case, the pressure drop between the inlet and outlet of the valve was about 350,000 ㎩ and local minimum pressure was calculated as about 3,000 ㎩ less than the vapor pressure of water at 25℃ Pressure variation in the valve was also compared for both cases.

림프절 전이를 동반한 직장암 환자들에서 Cyclooxygenase-2 발현의 임상적 의미

이형식(Hyung-Sik Lee),최영민(Youngmin Choi),허원주(Won-Joo Hur),김수진(Su-Jin Kim),김대철(Dae-Cheol Kim),노미숙(Mee Sook Roh),홍영습(Young-Seoub Hong),박기재(Ki-Jae Park) 대한방사선종양학회 2009 Radiation Oncology Journal Vol.27 No.4

목 적: 림프절 전이가 동반된 직장암 환자들에서 cyclooxygenase-2 (COX-2) 발현이 생존율에 미치는 영향을 조사하고자 한다. 대상 및 방법: 1998년부터 2004년까지 직장암으로 동아대병원에서 근치적 수술과 수술 후 방사선치료를 받은 환자들 중에서 림프절 전이가 동반된 경우를 대상으로 후향적분석을 하였다. 86명 중에서 수술 후 조직을 찾을 수 없는 3명, 악성 흑색종 1명, 진단 전후 2년 내에 위암과 폐암이 발생한 각 1명, 진단 시에 간 전이가 있었던 1명, 720cGy 후 방사선치료를 거부한 1명 등을 제외한 78명을 대상으로 분석하였다. COX-2에 대한 면역조직화학염색은 자동면역염색기로 하였고, 스캔한 후, 영상분석기를 이용하여 분석하였다. Kaplan-Meier 생존율 분석을 하였고, Logrank 검사로 유의성을 조사하였다.결 과: 면역조직화학염색에서 COX-2 양성이 62명(79.5%), 음성이 16명(20.5%)이었고, 양성도가 1, 2, 3인 환자들이 각각 6명(7.7%), 15명(19.2%), 41명(52.6%)이었다. 환자의 나이(60세 미만, 이상), 성별, 수술 방법(복회음절제술, 하위전방절제술), 세포의 분화도, 종양의 크기(5 cm 미만, 5 cm 이상), T병기, N병기, 병기(IIIa, IIIb, IIc), 등에 따른 COX-2 발현의 차이는 없었다. 전체 환자의 5년 생존율과 무병생존율은 각각 57.0%, 51.6%였다. COX-2 음성과 양성인 환자들의 5년 생존율이 72.9%와 53.0% (p=0.146), 5년 무병생존율이 72.7%와 46.3% (p=0.118)였다. COX-2 양성도가 0, 1, 2, 3인 환자들의 5년 생존율은 각각 72.9, 50.0 51.3, 53.1%였고(p=0.495), 5년 무병생존율은 각각 72.7, 50.0, 46.7, 45.1%였다(p=0.451). 5년 생존율은 악성종양 세포의 분화도, N병기, 병기, 등에 따라서, 5년 무병생존율은 N병기, 병기, 등에 따라서 유의한 차이가 있었다(p<0.05). 결 론: 림프절 전이가 동반된 직장암 환자에서 COX-2의 발현 여부와 정도는 생존율에 유의한 영향을 주지는 않았다. 하지만 향후 보다 많은 환자군을 대상으로 연구하여, COX-2 발현이 직장암의 예후에 미치는 영향을 규명해야 할 것으로 생각된다. Purpose: To assess the influence of cyclooxygenase-2 (COX-2) expression on the survival of patients with a combination of rectal cancer and lymph node metastasis. Materials and Methods: The study included rectal cancer patients treated by radical surgery and postoperative radiotherapy at the Dong-A university hospital from 1998 to 2004. A retrospective analysis was performed on a subset of patients that also had lymph node metastasis. After excluding eight of 86 patients, due to missing tissue samples in three, malignant melanoma in one, treatment of gastric cancer around one year before diagnosis in one, detection of lung cancer after one year of diagnosis in one, liver metastasis in one, and refusal of radiotherapy after 720 cGy in one, 78 patients were analyzed. The immunohistochemistry for COX-2 was conducted with an autostainer (BenchMark; Ventana, Tucson, AZ, USA). An image analyzer (TissueMine; Bioimagene, Cupertino, CA, USA) was used for analysis after scanning (ScanScope; Aperio, Vista, CA, USA). A survival analysis was performed using the Kaplan Meier method and significance was evaluated using the log rank test. Results: COX-2 was stained positively in 62 patients (79.5%) and negatively in 16 (20.5%). A total of 6 (7.7%), 15 (19.2%), and 41 (52.6%) patients were of grades 1, 2, and 3, respectively for COX-2 expression. No correlation was found between being positive of COX-2 patient characteristics, which include age (<60-year old vs. ≥60), sex, operation methods (abdominoperineal resection vs. lower anterior resection), degrees of differentiation, tumor size (<5 cm vs. ≥5 cm), T stages, N stages, and stages (IIIa, IIIb, IIIc). The 5-year overall and 5-year disease free survival rates for the entire patient population were 57.0% and 51.6%, respectively. The 5-year overall survival rates for the COX-2 positive and negative patients were 53.0% and 72.9%, respectively (p=0.146). Further, the 5-year disease free survival rates for the COX-2 positive and negative patients were 46.3% and 72.7%, respectively (p=0.118). The 5-year overall survival rates were significantly different (p<0.05) for the degree of differentiation, N stage, and stage, whereas the 5-year disease free survival rates were significant for N stage and stage. Conclusion: Being positive for and the degree of COX-2 expression did not have a significant influence on the survival of rectal cancer patients with lymph node metastasis. However, N stage and stage did significantly influence the rateof survival. Further analysis of a greater sample size is necessary for the verification of the effect of COX-2 expression on the survival of rectal cancer patients with lymph node involvement.

발열 강판을 포함하는 아연 도금 설비 내 유동장 해석

이형식(Hyung Sik Lee),곽동렬(Dong Lyel Gawk),이상호(Sang Ho Lee) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6

Numerical analysis has been carried out to investigate the flow and heat transfer characteristics in Zinc quenching systems for steel sheets. Zinc temperature has large influence on the quality of outputs. Modeling results are compared for various flow rates of air coolant considering the conjugate heat transfer in the main parts of systems. It is found that average temperatures of air coolant in outlets are 107 ℃ and 263 ℃ for volume flow rates of 600 ㎥/h and 4,080 ㎥/h respectively.

SCK 선암 세포주에서 방사선에 의한 apoptosis와 세포 주기

이형식(Hyung Sik Lee),박홍규(Hong Kyu Park),허원주(Won Joo Hur),서수영(Su Yeong Seo),이상화(Sang Hwa Lee),정민호(Min Ho Jung),박헌주(Heon Joo Park),송창원(Chang Won Song) 대한방사선종양학회 1998 Radiation Oncology Journal Vol.16 No.2

목 적 : SCK 선암 세포주에서 방사선 조사에 의해 일어나는 apoptosis와 세포 주기와의 연관성을 규명하고자하였다. 대상 및 방법 : SCK 선암 세포주를 apoptosis의 통상적인 정성 분석 방법인 agarose gel electrophoresis 방법을 이용하여 방사선 조사량과 배지 pH 환경과의 연구에서 2-12Gy의 방사선 조사량과 pH 7.5 및 6.6의 배양 배지 조건하에서 다양한 배양 시간의 경과에 따른 DNA fragmentation의 지표인 laddering을 관찰하였다. 실험 조작으로 apoptosis가 유발된 세포군을 정량적으로 분석하고 세포 주기 분석을 위해 FACScan을 이용하였다. 결 과 : apoptosis가 왕성히 발현되었던 pH 7.5 배지에서 배양하였던 세포에서는 방사선 조사직후부터 G2/M phase의 세포들의 분획이 증가하기 시작하여 12시간째 약 70%까지의 최고치를 보인 후 36시간째에 방사선을 조사하지 않았던 상태의 분획으로 정상화되었다. 하지만 pH 6.6 배지에서 배양하였던 세포에서의 G2/M phase의 세포들의 분획의 증가는 pH 7.5 배지에서 배양하였던 세포들에 비해 비교적 천천히 일어나고 그 최고치도 24시간째에 약 45%로 관찰되었다. 특이한 것은 G2/M phase의 세포들의 분획이 그 이후 감소되는 정도가 pH 7.5 배지에서 배양하였던 세포들에 비해 미약하여 48시간 배양 이후에도 약 30-35%의 세포는 G2/M phase의 세포들의 분획으로 관찰되었다. 결 론 : 연구자들은 이러한 현상이 세포들이 G2/M phase에서 많은 양의 세포들이 집적되어 세포주기를 순환하지 못하는 G2/M arrest 현상으로 이해하였다. 세포 내외의 산성환경 상태에서 방사선을 조사 받은 SCK 종양세포는 G2/M arrest 상태가 지속되며 이는 post- mitotic apoptosis를 억제한다고 추론하였다. Purpose : The relationship between environmental pH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. Material and Methods : Mammary adenocarcinoma cells of A/J mice(SCK cells) in exponential growth phase were irradiated with a 137Cs irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at 37℃ for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Results : The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in G2/M phase rapidly increased to about 70% at 12 h after an exposure to 12Gy and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in G2/M increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about 45% at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as 30-35% of the cells were still in the G2/M phase 48h after irradiation. The percent age of cells in G1 phase then increased as the G2/M arrest began to recede. The radiation-induced G2/M arrest in pH 6.6 medium lasted markedly longer than that in pH 7.5 medium. Conclusion : Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced G2/M arrest is prolonged in an acidic environment indicating that the suppression of radiation- induced apoptosis and prolongation of radiation-induced G2/M arrest in an acidic environment are related.

골격성 III급 부정교합을 동반한 악교정수술 환자에서 수술 전후의 하악기능 변화에 관한 실험적 연구

이형식(Hyung Sik Lee),박영철(Young Chel Park) 대한치과교정학회 1992 대한치과교정학회지 Vol.22 No.1