타타늄의 열처리 조건에 따른 동전위 양극분극특성 및 표면 미세구조 변화

주동현,이용렬,정영화,양홍서,박상원,이도재,송호준,박영준 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.2

The corrosion resistance of metallic implants is essential for successful implant osseointegration. Moreover, the implant surface should have appropriate surface roughness for the attachment of the osteoblast and collagen fibrils. When titanium is exposed to air a thermodynamically very stable oxide film is formed at once. This oxide is very thin and yet it protects the metal from corrosion instantaneously. However, the oxide would not be ideal, and it would be supposed that the state of oxide film would be various by the different conditions when it is formed. The objective of this study was to evaluate the electrochemical properties and surface microstructural changes of titanium after passivation treatment or exposure to high heat (in vacuum or in air). ASTM grade 2 commercially pure titanium (Ti) disks of 10㎜ diameter were wet ground and polished with 240 and 600 grit SiC, and then ultrasonically cleaned with distilled water and ethanol. Cleansed as-received samples (As-R group) were passivated with 30% nitric acid solution at 50℃ for 15 minutes to make the Pas group. The Std-V samples were made by treating the Ti disks in vacuum quartz tube (10^-8 Torr) at 530℃ for 40 min for stress relieving, followed by annealing at 700℃ for 90 min, and then slow cooling to room temperature. The Std-A samples undergo identical procedure as the Std-V group except that it is done in air. For 530℃-V samples, Ti disks were heated at 530℃ for 40 minutes and slow cooled to room temperature. The 1000℃-V samples were produced by heating Std-V specimens again at 1000℃ for 2 hr, followed by cooling to room temperature. 530℃-A and 1000℃-A samples were also prepared. Potentiodynamic anodic polarization measurement, SEM, AFM and XRD analysis were performed to evaluate the effects of the various treatments. The difference in the mean values of E_corr between groups showed statistically significant difference (P<0.05), but that of I_corr did not show significance (P>0.05). When Ti surface was passivated there was a shift of corrosion potential (E_corr) in the noble direction and a lower corrosion current density (I_corr) value. Std-A samples showed most noble E_corr value among the tested groups. 530℃-V samples showed more noble E-corr than other tested groups except Std-A group. 1000℃-V samples showed more noble E-corr than those of Std-V sample. In the case of Std-, 530℃- and 1000℃-groups, -A sub-groups showed better corrosion resistant characteristics than -V sub-groups in regard to E-corr and I_corr values. In the SEM observations, the surfaces of the As-R samples showed only scratch line on smooth surface. In Pas samples, thick oxide layer covered the surface under high magnification observation. 530℃-A samples were covered by oxide granules, and Std-A samples had 25~50 nm-thick acicular oxides. The 1000℃-A samples were covered by coarse oxide crystals with a granule diameter of 0.1~0.6 μm having a gross appearance of milky white color, which was identified by XRD as a rutile. On the other hand, 1000℃-V samples showed an Widmansta¨tten structrue of which the orientation of the lattice is formed along crystallographic planes of the parent crystals. On the AFM observation, 530℃-A samples showed RMS roughness of 79.38 nm which is 5 times rougher than those of the As-R samples. Std-A sample had a roughness of 330.47 nm which is about 20-times rougher than that of the As-R sample. 1000℃-A samples were covered by coarse granular oxides and the roughness were about 0.56 μm. Vacuum sub-group samples showed a more smooth surface than air sub-group samples, and the oxide film was more dense. Due to variability of the surface treatment and heat treatment conditions, the process of the oxide formation seems to be affected thereby making the corrosion properties and surface micro-morphology different. However, more various electrochemical analysis together with surface analysis, and an investigation for the effects of those on the osteoblast cell adhesion and calcium phosphate apposition are needed for the improvement of the osseointegration rates of the titanium implants.

NOD/SCID 마우스 모델을 이용한 인간 제대혈 혼합이식에서의 생착 양상 분석

정양조,김동욱,조빈,강영주,박보배,김혜정,김태규,오일환 대한조혈모세포이식학회 2002 대한조혈모세포이식학회지 Vol.7 No.2

연구배경: 제대혈은 골수에 비해 많은 장점을 가지고 있음에도, 이식 후 성적에 있어 총세포수에 의해 좌우되며, 한 개의 태반으로부터 얻을 수 있는 총세포수의 한계가 있어 주로 소아에 국한되고 있다. 따라서 제대혈 응용의 확대를 위해 생착량을 늘이기 위한 방법으로 다중공여자에 의한 제대혈 혼합이식을 늘일 수 있는지 연구하기 위하여, 본 연구에서는 주조직적합성 형별로 조합된 제대혈을 NOD/ SCID 생쥐에 이식하는 방법으로, 혼합생착의 가능성을 연구하였다. 방법: 조합된 2개 공여자로부터 얻어진 제대혈들을 단일이식 및 혼합이식하여, 혼합이식된 숙주에 생착된 세포를 PCR-SSOP 방법을 사용하여 공여자 별로 추적하였다. 또한 각 공여자세포의 상대적 생착비율을 대조군인 단일제대혈 이식에서 얻어진 생착량과 비교하는 정량적 비교도 함께 하였다. 결과: 총단핵구를 혼합이식한 실험군에서는 주조직적합성의 일치도에 관계없이 한쪽공여자의 세포가 다른쪽에 비해 우세한 편향생착을 보였다. 그러나 임파구를 비롯한 Lineage 양성세포를 제거한 실험군에서는 주조직적합성의 불일치에도 불구하고 뚜렸한 생착의 공존이 관찰되었다. 결론: 본 연구는 제대혈의 생착량을 증가를 목적으로 총단핵구를 혼합이식할 경우 한쪽공여자의 세포에 의해 편중되며, 이것을 이식 후 생착과정에서의 두 종류의 세포의 경쟁에 의해 초래된다는 것을 보이고 있다. 또한 이러한 경쟁은 제대혈에 포함되어 있던 임파구들에 의한 것이며, 생착공존을 위하여는 공여자간 주조직적합성의 일치도 보다, 임파구의 제거가 더 중요하다는 것을 보여주고 있다. Background: Although umbilical cord blood (UCB) has been an attractive alternatives for bone marrow cells, application is limited to pediatric case due to limitation in total number of nucleated cells, that is a single most important factor for outcomes of UCB transplantation. Therefore, increasing overall engraftment by mixed transplantation of UCB derived from multiple donor should comprise one strategy to circumvent the posed limitation of UCB transplantation. In order to investigate the feasibility of establishing co-engraftment by multi-donor UCB cells, we carried out a xenotransaplantation study using NOD/SCID mice for systemic analysis of results on the input-based control of single unit transplantation. Methods: UCB units with various extent of HLA-matchings were co-transplanted into NOD/SCID mice along with single unit transplantation control. The relative contributions of engraftment by cells from each donor-derived were analyzed by HLA polymorphism using PCR-SSOP. Results: In all HLA-based mixed transplantation of total nucleated UCB cells, engraftment of one donor predominated over the other despite that equivalent amount of engraftments were achieved by single donor transplantation. When lineage depleted UCB units were co-transplanted, significant degree of co-engraftments were observed regardless of HLA disparity. Conclusion: Our result show that one donor cells dominate over the other in mixed UCB transplantation and that it is due to competition between donor cells during post-transplantation process. Our results suggest that immune cells contained in UCB unit mediate such competitioin and that 6 locus HLA matching would not be sufficient to prevent the competition.

이미지 검색을 위한 관심영역의 요소추출과 데이터 변환 연구

강문주,양동일,김덕은,최형진 강원대학교 정보통신연구소 2006 정보통신논문지 Vol.10 No.-

In this paper we designed the content-based image system. It discovers the characteristic value of color area for the existing image, when any user establishes the special interesting region for the question images. And we designed the system to be able to search the similar image of the interesting region, compared with the table that saved the characteristic value of moment which is unchangeable for the size and the rotation of form. In this paper, we suggest the image search model based on neural network. This is able to seek for the aimed image through the feedback to search the nonlinear relations by the method of searching content-based image using SOM neural network. We make use of the Precision and the Recall that are used for the system evaluation using the similar matching method in general. As a result of the evaluation of the content-based image system, we can reduce the time and memory to find out the feature value of the image that is meaningless in the general images.

이미지 검색을 위한 관심영역의 오소추출과 데이터 변환 연구

강문주,양동일,김덕은,최형진 강원대학교 정보통신연구소 2006 정보통신논문지 Vol.10 No.-

In this paper we designed the content-based image system. It discovers the characteristic value of color area for the existing image, when any user establishes the special interesting region for the question images. And we designed the system to be able to search the similar image of the interesting region, compared with the table that saved the characteristic value of moment which is unchangeable for the size and the rotation of from. In this paper, we suggest th image search model based on neural network. This is able to seek for the aimed image through the feedback to search the nonlinear relations by th method of searching content-based image using SOM neural network. We make use of the Precision and the recall that are used for the system evaluation using the similar matching method in general. As a result of the evaluation of the content-based image system, we can reduce the time and memory to find out the feature value of the image that is meaningless in the general images.

산국의 수량과 유효성분에 대한 NPK의 효과

이경동,양민석,정연규,손보균,조주식,이성태,김필주 한국농화학회 2003 Applied Biological Chemistry (Appl Biol Chem) Vol.46 No.2

본 연구는 3요소(N-PO_2O_5-K_2O)처리가 산국(Chysanthemum boreale M.)의 수량과 유효성분에 미치는 효과를 조사하여 효과적인 재배시스템을 개발하고자하였다. 처리구는 무처리, NPK(250-160-160), NK(250-0-160), PK(0-160-160kg/ha)의 5처리로 설정하여 산국을 재배한 결과, 건물수량은 NPK처리구가 PK처리구에 비하여 4.0배의 증수가 있었으며, 다른 처리구보다 무기이온의 흡수율, 생육 및 수량에서 NPK처리구가 가장 우수하였다. 식용으로 많이 쓰이는 꽃의 주요 아미노산은 proline, glutamic acid과 aspartic acid이였고, 다른 처리구들에 비하여 NPK처리구가 높은 함량을 보였다. 혈압강하효과가 우수한 cumambrin A는 PK처리구에 비하여 NPK처리구가 6.2배의 증수효과가 있었다. NK처리구는 NP처리구보다 cumambrin A의함량을 높이기 위해서는 인산의 시용보다 칼리의 시용이 더 요구되며, 야외포장에서의 인산과 칼리의 적정 시비량의 설정이 필요하다고 판단된다. To establish the fertilization condition to increase the productivity of Chrysanthemum boreale M. with high quality, the effects of three nutrients (N, P, K) on the yields and the effective components were investigated in the pot scale. NPK was applied by chemical fertilizers with N-P_2O_5-K_2O = 250-160-160 kg/ha as a main treatment, and NP (N-P_2O_5 = 250-160 kg/ha), NK (N-KO = 250-160 kg/ha), and PK (PO_2-KO_5 = 160-160 kg/ha) treatments were settled as comparison. Dry yields of C. boreale M. was increased significantly to 4 fold higher by nitrogen. Nitrogen increased apparently plant growth and inorganic nutrient uptake. In the flower, which is most useful and edible part as a herbal medicine, main amino acids were glutamic acid and aspartic acids, and the total content was increased significantly by three elements of application. In addition, the content of cumambrin A, which is known to have the effect of blood-pressure reduction, was increased source to 6.2 times by nitrogen higher than that in PK treatment. Potassium was more effective in biosyndiesis of cumatnbrin A than phosphorus, but the biological pathway was not clear, still.

골수염의 진단에 있어서의 Tc-99m Hexamethylpropylene amine oxime 백혈구 스캔의 임상적 유용성

최상호,김양수,정준원,정진원,추은주,서동대,배인규,양승오,우준희,류지소 대한화학요법학회 2001 대한화학요법학회지 Vol.19 No.1

배경 : 골수염의 진단에 있어 Technetium-99m을 이용한 삼상 골스캔(Tc-99m MDP스캔)은 단순방사선 검사상 정상소견을 보이는 경우에 쓰이는 1차적 검사로 매우 높은 민감도를 보인다. 그러나 Tc-99m MDP 스캔은 골절이나, 정형외과적 삽입물, 신경병적 관절병변과 같이 뼈의 재형성이 증가되는 상황에서도 양성소견을 보여 특이도가 낮은 단점이 있다. 이러한 단점을 보완하고자 골수염의 진단에 있어 Tc-99m HMPAO 백혈구 스캔의 유용성을 알아보고자 하였다. 대상 및 방법 : 골수염이 의심되어 Tc-99m HMPAO 백혈구 스캔을 시행했던 15명의 의무기록을 후향적으로 분석하였다. 골수염의 확진은 임상관찰 소견과 배양검사 결과와 병리소견을 기준으로 하였다. 결과 : 골수염의 진단에 있어 Tc-99m HMPAO 백혈구 스캔의 민감도와 특이도는 각각 100%와 78%였고 Tc-99m HMPAO 스캔의 경우는 100%와 18%였다. 가장 흔한 원인균은 methicillin-resistant S. aureus였다. Tc-99m MDP 스캔에서 양성소견을 보였던 환자중 3명의 환자가 Tc-99m HMPAO 백혈구 스캔에서 음성 소견을 보였으며 이 환자들은 추적관찰상 골수염이 없는 것으로 확인되었다. 결론 : Tc-99m HMPAO 백혈구 스캔은 골수염의 존재를 진단하는데 있어 민감도와 특이도가 높으며, 특히 뼈의 재형성이 증가되어 Tc-99m MDP 스캔의 특이도가 낮게 나타나는 상황에서 유용하리라 사료된다. Background Three phase bone scintigraphy, performed with technetium-labeled diphosphonates (Tc-99m MDP scan), is the very sensitive radionuclide procedure of choice for diagnosing osteomyelitis. But, Tc-99m MDP scan is less specific when bone remodeling is increased. To overcome this limitation, we evaluated the diagnostic value of technetium-99m hexamethylpropyleneamine oxime (HMPAO) labeled leukocyte scan in osteomyelitis. Methods : We retrospectively reviewed 15 patients with suspected osteomyelitis who performed Tc-99m HMPAO labeled leukocyte scan. The diagnosis of osteomyelitis was based on clinical course and bacterial culture, and pathologic findings. Results The sensitivity and specificity of Tc-99m HMPAO leukocyte scan was 100% and 78%, and those of Tc-99m MDP scan was 100% and 18%, respectively. The most common organism was Methicilein-Resistant S. aureus. Among the patients that showed persistent accumulation on Tc-99m MDP scan, three patients showed no uptake on Tc-99m HMPAO leukocyte scan and these patients were confirmed that had no osteomyelitis. Conclusion : Tc-99m HMPAO leukocyte scan is a useful test for determining the presence or absence of osteomyelitis, especially under condition that bone remodelin is increased.

Lithium‐Sulfur Batteries: An Advanced Lithium‐Sulfur Battery (Adv. Funct. Mater. 8/2013)

Kim, Junghoon,Lee, Dong‐,Ju,Jung, Hun‐,Gi,Sun, Yang‐,Kook,Hassoun, Jusef,Scrosati, Bruno WILEY‐VCH Verlag 2013 Advanced functional materials Vol.23 No.8

<P>On page 1076, Yang‐Kook Sun, Jusef Hassoun, Bruno Scrosati, and co‐workers report and characterize a hard carbon spherules‐sulfur electrode that is prepared by impregnation of crystalline sulfur into the carbon spheres through melting and thermal treatment. This material demonstrates very high capacity and rate capability, and is therefore proposed as a new generation cathode to drive electric vehicles over a long range. </P>

대퇴골 전자간 골절을 동반한 고령의 환자에서 시행한 슬관절 전치환술

고덕환,김동헌,김규현,신주용,양준호 건국대학교 의과학연구소 2001 건국의과학학술지 Vol.11 No.-

Purpose: To analyze the clinical results of total knee arthroplasty In elderly patients who had arthritic knees and intertrochanteric fractures. Materials and Methods: From fan 1992 to March 1999, 27 cases of the patients with arthritic knees and associated intertrochanteric fractures were treated by total knee arthroplasties and we evaluated the patients by Knee Score of American Knee Society. Results: Flexion contracture was improved from 10.3 degree to 5.2 degree, KSS score was improved from 57.4 points to 78.6 points, authors' evaluation system score was improved from 50.3 points to 73.2 points. Conclusion: In elderly patients with arthritic knees and associated intertrochanteric fractures, total knee arthroplasty seemed to decrease the rehabilitation time and allow earl weight bearing, so provide an improvement in quality of life.

Alkylhalide가 Mouse의 LDH isozyme 분포에 미치는 영향 : Cellulose Acetate Electrophoresis Method

권미경,김영옥,박은주,이동화,이명미,이문희,이양자 曉星女子大學校 藥學大學 學生會 1988 曉星藥誌 Vol.4 No.-

The effect of Carbontetrachloride administration on Lactatedehydrogenase isozyme patterns were analyzed by cellulose acetate electrophoresis for the brain, heart, kidney, lung, liver and mouse muscle. Each other tissue was found to have a characteristic distribution of these isozymes. At normal condition, aerobic tissue such as brain, heart, kidney, and lung were found to have all five isozymes from LDH_1 to LDH_5, while anaerobic tissues such as liver and muscle were found to have superiorly LDH_5 The toxicity of Carbontetrachloride administration was most prominence in the liver, and lung toxicity was occured also.

열공형과 비열공형 피질하 혈관성 치매에서 위험인자의 차이에 관한 비교 연구

배희준,정지향,유경호,나덕렬,김상윤,최경규,양동원,손의주,이상도,김재우,박경원,김응규,이재홍,박미영,한일우,함동석,최문성,하충건,최성혜,이애영,이병철,한설희 대한치매학회 2003 Dementia and Neurocognitive Disorders Vol.2 No.2

Backgrounds and Objectives: Vascular dementia is a group of dementing disoders arising from various stroke syndrome. Among these. subcortical ischemic vascular dementia (SIVD) is regarded as a relatively distinct clinical entity. However, MRI patterns of SIVD are not homogenous. In some patients, lacunes are dominant, and in others, subcortical white matter changes are. This study was designed to compare risk factor profiles between SIVD with and without multiple lacunes. Methods: We divided 47 subjects (22 males, mean age. 68 years) recruited from VADAPET (Multicenter Trial For Evaluation Of The Changes In the PET Images Of Subcortical Vascular Dementia Patient) study into two groups one with more than 5 lacunes in deep gray matter (lacune group) and the other with 5 or less(non-lacune group) Clinical characteristics and laboratory findings of two groups were compared. Results: Nineteen of 47 patients (40%) belonged to the lacune group. The lacune and non-lacune groups d d not differ in the following variables: age, hypertension, diabetes mellitus, hyperlipidemia heart disease, history of stroke or TIA, history of trauma or major surgery, family history of hypertension stroke, or dementia, age at diagnosis of dementia, body mass index, white blood cell count, ESR, CRP, fibrinogen, hemoglobin A1C, total cholesterol. LDL cholesterol creatinine, proteinuria, glucosuria, and microhematuria. However, male sex, smoking alcohol. hemoglobin, and HDL cholesterol were possibly associated more with lacune group SIVD than with non-lacune group (p<0 1) Multivariate analyses revealed that smoking, hemoglobin, and HDL cholesterol were independent predictors of SIVD with multiple lacunes Conclusion: Our study suggests that SIVD with multiple lacunes may be significantly different in smoking habits hemoglobin, and HDL cholesterol from SIVD without multiple lacunes.