방사선조사가 Streptococcus mutans에 미치는 영향

안기동,김규태,최용석,황의환,Ahn, Ki-Dong,Kim, Gyu-Tae,Choi, Yong-Suk,Hwang, Eui-Hwan 대한영상치의학회 2007 Imaging Science in Dentistry Vol.37 No.1

Purpose : To observe direct effect of irradiation on cariogenic Streptooccus mutans. Materials and Methods : S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, transmission electron microscopy, RT-PCR, and SDS-PAGE, respectively. Results : After irradiation with 10 and 20Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated 5. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased, a higher number of cells showed thickened cell wall and cell membrane and Iysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spap between cells with and without irradiation of 40Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. Conclusion : These results suggest that irradiation affects the cell Integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

방사선조사가 Streptococcus mutans에 미치는 영향

안기동,김규태,최용석,황의환 대한구강악안면방사선학회 2007 Imaging Science in Dentistry Vol.36 No.1

Purpose : To observe direct effect of irradiation on cariogenic Streptooccus mutans. Materials and Methods : S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, transmission electron microscopy, RT-PCR, and SDS-PAGE, respectively. Results : After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased, a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. Conclusion : These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium. (Korean J Oral Maxillofac Radiol 2007; 37: 35-43)

채혈실 CQI 개선활동

안기동,박현정,전현숙,안정연,송주연,이남엽,조석제,김문진 한국의료QA학회 2007 가을학술대회 Vol.2007 No.3

방사선조사가 당뇨 백서의 측두하악관절에 미치는 영향

안기동,황의환,이상래 대한구강악안면방사선학회 2004 Imaging Science in Dentistry Vol.34 No.2

Purpose : To investigate the histopathological changes in the temporomandibular joint in streptozotocin-induced diabetic rat following irradiation. Materials and Methods : Sprague-Dawley rats weighing about 250 gm were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control group were injected with citrate buffer only. After 5 days, the head and neck region of the rats in diabetic- irradiated group were irradiated with single absorbed dose of 10 Gy. The rats were killed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimen including the temporomandibular joint were sectioned and observed using a histopathological method. Results : In the diabetic group, severe bone resorption in the mandibular condyle was observed throughout the period of experiment. Necrosis of bone marrow and trabeculae was observed at 28 days after diabetic state. Atrophy and fibrosis in the retrodiscal tissue was gradually progressed during the time of the experiment. In the diabeticirradiated group, severe bone resorption in the mandibular condyle was observed during the early experimental phases, but regeneration of bone marrow was initiated at 14 days after diabetic state and irradiation. Also, calcification of abnormal trabeculae was observed at 28 days after diabetic state and irradiation. The retrodiscal tissue was degenerated in the early experimental phases, but it had been gradually regenerated during the experimental time. Conclusion : This experiment suggests that bone resorption and degeneration in the mandibular condyle are caused by the induction of diabetes, and abnormal bone formation is induced after irradiation in diabetic state.

합천 삼가식 다곽분 연구

안기동 한국고고학회 2023 한국고고학회 학술대회 Vol.2023 No.-

공혈자 혈액에서의 C 형 간염 항체 양성율

안기동 ( Gi Dong Ahn ),검광현 ( Kwang Hyeon Kim ),김용호 ( Yong Ho Kim ),함건주 ( Kun Ju Hahm ) 대한임상검사과학회 1990 대한임상검사과학회지(KJCLS) Vol.22 No.1

In order to elucidate seroprevalence of the hepatitis C virus antibody (Anti- HCV) in health blood donors, the authors examined serum ALT, HBsAg, Anti-HBc and anti-HCV(Asan, Fujirebio - RPHA, Abbott-RIA, Abbott-EIA) in 600 cases of blood donors (male : 544, female : 56) from July 1 to August 31, 1990. The results ·obtained were summarized as follows: 1. The seroprevalence of anti- HCV in 600 healthy blood donors was 0. 67% (4/600). 2. The seroprevalence of anti- HCV is increased with increase of serum alanin aminotransferase (ALT) values with anti- HBc positive cases than anti- HBc negaive cases, and with HBsAg positive cases than HBsAg negative cases(P>0.05). 3. Anti-HBc positive rate was 55.0%(330/ 600) and positive rate was increased as age increased, serum ALT value increased. 4. HBsAg positive rate was 6.0% (36/600) and rate for male was statistically significant higher than that for female (P < 0. 05) and positive rate was increased as serum AL T value increased (P < 0.01). On the basis of the results above, HBsAg, serum AL T tests in blood donors can prevent hepatitis C virus infection in about 50 percents. For the purpose of the prevention of HCV infection in the other donors and blood loss, it will be n~eded to screen the serum anti- HCV in whole blood donors.

Set Covering 기반의 대용량 오믹스데이터 특징변수 추출기법

마정우(Zhengyu Ma),안기동(Kedong Yan),김광수(Kwangsoo Kim),류홍서(Hong Seo Ryoo) 한국경영과학회 2014 韓國經營科學會誌 Vol.39 No.4

In this paper, we dealt with feature selection problem of large-scale and high-dimensional biological data such as omics data. For this problem, most of the previous approaches used simple score function to reduce the number of original variables and selected features from the small number of remained variables. In the case of methods that do not rely on filtering techniques, they do not consider the interactions between the variables, or generate approximate solutions to the simplified problem. Unlike them, by combining set covering and clustering techniques, we developed a new method that could deal with total number of variables and consider the combinatorial effects of variables for selecting good features. To demonstrate the efficacy and effectiveness of the method, we downloaded gene expression datasets from TCGA (The Cancer Genome Atlas) and compared our method with other algorithms including WEKA embeded feature selection algorithms. In the experimental results, we showed that our method could select high quality features for constructing more accurate classifiers than other feature selection algorithms.

포스터 2 : 비예기항체 동정검사에서 Anti-Luª의 검출 사례

성성경,손혜수,조석제,김선재,석주호,안기동,오승환,이자영,김혜란 대한임상병리사협회 2011 임상수혈검사학회 발표자료집 Vol.2011 No.-

배경 : Anti-Luª는 자연항체로써 실온에서 잘 반응하며, 37℃에서 반응하는 일은 드물고, 부분응집(mixed field agglutination)을 일으키는 특징이 있다. Lua항원 빈도는 한국인에서 0%이며 백인과 흑인에서도 0.1%로 매우 낮고, 환자의 혈청에서 검출되어도 수혈부작용은 거의 없는 것으로 보고되어 있다. 본원 혈액은행의 비예기항체 동정검사에서 Anti- Lua가 검출되어 그 사례를 보고하고자 한다. 증례 : 환자는 봉소염으로 본원 응급실을 내원하여 혈액형 및 비예기항체 선별검사를 실시하였다. 비예기항체 선별검사 결과는 음성이었고, 3일 후의 결과도 음성이었다. 3번에걸쳐 괴사조직을 봉합하는 수술을 실시하면서 농축적혈구를 수혈 받았으며, 3주 후 복강경 담낭 절제술로 인한 수혈을 위해 의뢰된 비예기항체 선별검사에서 양성이 나와 동정검사를 실시하였다. 동정된 결과는 Anti-Lua였는데 검출빈도가 매우 낮은 항체이므로 동정 혈구의 Lot No.를 달리하여 재검을 실시하였다. 재검에서도 동일한 항체가 동정되어 항원검사를 실시한 결과 Lua항원 음성으로 나와 Anti-Lua임을 확인하였다. 이후 실시된 3번의 비예기항체 선별검사에서 모두 음성으로 나와 처음에는 역가의 일시적인 감소로 생각하였으나, Lot No.에 따라 선별혈구의 조합이 다르다는 것을 알게 되어 비예기항체 동정검사를 실시한 결과 Anti Lua가 다시 동정되었다. 결론 및 고찰 : 비예기항체 선별검사가 처음 의뢰되었을 때의 선별혈구 Lua항원조합은 I,II 모두 음성이므로 Anti Lua가 있다하더라도 선별검사 결과는 음성으로 나오게 된다. 그후 I 혈구에 Lua항원이 포함되어있는 Lot의 시약에서 1+정도의 양성을 보였고 다시 I, II둘 다 항원 음성인 선별혈구였다. 이와 같은 사례로 볼 때 환자 혈청 내에 비예기항체가 존재한다 하더라도 선별혈구의 항원 유무에 따라 검출 기회를 놓칠 수 있는 검사 상 한계가 있다. 본원에서 동정된 Anti-Lua는 수혈에 의한 면역항체라기 보다 환자가 선천적으로 가지고있는 자연항체일 가능성이 높을 것으로 생각된다.