슬관절 전치환술에서 후방 안정 임플란트의 오정렬이 경골 기둥에 미치는 영향

김상훈,안옥균,배대경,김윤혁,김경수,이순걸,Kim, Sang-Hoon,Ahn, Ok-Kyun,Bae, Dae-Kyung,Kim, Yoon-Hyuk,Kim, Kyung-Soo,Lee, Soon-Gul 대한의용생체공학회 2007 의공학회지 Vol.28 No.1

Recently, it has been reported that the posterior stabilized implant, which is clinically used for the total knee replacement (TKR), may have failure risk such as wear or fracture by the contact pressure and stress on the tibial post. The purpose of this study is to investigate the influence of the mal alignment of the posterior stabilized implant on the tibial post by estimating the distributions of contact pressure and von-Mises stress on a tibial post and to analyze the failure risk of the tibial post. Finite element models of a knee joint and an implant were developed from 1mm slices of CT images and 3D CAD software, respectively. The contact pressure and the von-Mises stress applying on the implant were analyzed by the finite element analysis in the neutral alignment as well as the 8 malalignment cases (3 and 5 degrees of valgus and varus angulations, and 2 and 4 degrees of anterior and posterior tilts). Loading condition at the 40% of one whole gait cycle such as 2000N of compressive load, 25N of anterior-posterior load, and 6.5Nm of torque was applied to the TKR models. Both the maximum contact pressure and the maximum von-Mises stress were concentrated on the anterior-medial region of the tibial post regardless of the malalignment, and their magnitudes increased as the degree of the malalignment increased. From present result, it is shown that the malalignment of the implant can influence on the failure risk of the tibial post.

갈색세포종과 복부 부신경절종의 임상적 특성 분석

김상훈,정승필,이정희,김지영,최민영,이세경,최준호,이정언,김지수,남석진,양정현<SUP>1<.SUP>,김정한,Sang-Hoon Kim,Seung-Pil Jung,Jeong-Hee Lee,Ji-Yeong Kim,Min-Yeong Choi,Se-Kyung Lee,Jun-Ho Choe,Jeong-Eon Lee,Jee Soo Kim,Seok-Jin Nam,Jung- 대한갑상선-내분비외과학회 2011 The Koreran journal of Endocrine Surgery Vol.11 No.4

과산화수소 증기를 이용한 다양한 쿠폰 표면의 Geobacillus Stearothermophilus 아포 제독조건

김상훈,정경화,김세계,채영규,김윤기,황현철,김민철,박명규,류삼곤,Kim, Sang Hoon,Jung, Kyoung Hwa,Kim, Se Kye,Chai, Young Gyu,Kim, Yun Ki,Hwang, Hyun Chul,Kim, Min Cheol,Park, Myung Kyu,Ryu, Sam Gon 한국군사과학기술학회 2013 한국군사과학기술학회지 Vol.16 No.4

Biological decontamination means the removal of microorganisms from the inanimate object such as building or equipment. In this study, hydrogen peroxide vapor efficacy test using VHP 1000ED system(Steris LifeSciences) were conducted for G. stearothermophilus spore with agent materials(aluminum, stainless steel, poly-carbonate, viton, silicone, kapton and glass). Total recovered spores exposed to hydrogen peroxide vapor(1.0 g/min) during 7, 15, 30, 60 min were calculated. As a result, all agent materials were totally decontaminated within 60 min at 1.0 g/min concentration with 35% hydrogen peroxide vapor. Finally, we could confirmed that hydrogen peroxide vapor possess sporicidal capacity of G. stearothermophilus and found the optimum decontamination conditions with VHP1000ED system.

과산화수소 제독 과정에서의 탄저균 전사체 분석

김상훈,김세계,정경화,윤성녀,김윤기,김민철,류삼곤,이해완,채영규,Kim, Sang Hoon,Kim, Se Kye,Jung, Kyoung Hwa,Yoon, Sung Nyo,Kim, Yun Ki,Kim, Min Cheol,Ryu, Sam Gon,Lee, Hae Wan,Chai, Young Gyu 한국군사과학기술학회 2015 한국군사과학기술학회지 Vol.18 No.4

Decontamination of biological agents utilizes hydrogen peroxide($H_2O_2$) for its effectiveness and safeness. Bacillus anthracis is a major target for $H_2O_2$ decontamination. To assess the effect of $H_2O_2$ on B. anthracis and identify biomarkers for decontamination, whole transcriptomic profiling of $H_2O_2$-treated B. anthracis was performed. Here we identified deregulation in stress response genes, transcription factors and cellular homeostasis genes. We also found that expression of antisense RNAs increased in B. anthracis during decontamination. We postulate that B. anthracis prioritizes survival and adaptation in response to $H_2O_2$ treatment by changing its gene expression pattern.

타이타늄의 표면거칠기가 도재의 결합강도에 미치는 영향

김상훈,방몽숙,양홍서,박상원,박하옥,임현필,오계정,Kim, Sang-Hun,Vang, Mong-Sook,Yang, Hong-So,Park, Sang-Won,Park, Ha-Ok,Lim, Hyun-Pil,Oh, Gye-Jeong 대한치과보철학회 2007 대한치과보철학회지 Vol.45 No.2

Statement of problem: Titanium has many advantages of high biocompatibility, physical properties, low-weight, low price and radiolucency, but it is incompatible with conventional dental porcelain due to titanium's oxidative nature. Many previous studies have shown that they used the method of sandblast for surface treatment prior to porcelain application, the researches are processing about the method of acid etching or surface coating. Purpose: The purpose of this research is to study the effect on bond strength of surface roughness between titanium and porcelain with the same surface topography. Material and method: In this study, we evaluated the bond strength by using 3-point bending test based on ISO 9693 after classified 8 groups - group P : polished with #1200 grit SiC paper, group S10 : $1.0{\mu}m$ surface roughness with sandblasting, group S15 : $1.5{\mu}m$ surface roughness with sandblasting, group S20 : $2.0{\mu}m$ surface roughness with sandblasting, group S25 : $2.5{\mu}m$ surface roughness with sandblasting, group S30 : $3.0{\mu}m$ surface roughness with sandblasting, group S35 : $3.5{\mu}m$ surface roughness with sandblasting, group E : $1.0{\mu}m$ surface roughness with HCl etching. Results: Within the confines of our research, the following results can be deduced. 1. In the results of 3-point bending test, the bond strength of sandblasting group showed significant differences from one of polishing group, acid etching group(P<.05). 2. The bond strength of sandblasting groups did not show significant differences. 3. After surface treatments, the group treated with sandblasting showed irregular aspect formed many undercuts, in the SEM photographs. The bond strength of sandblasting group was higher than 25 MPa, the requirement of ISO 9693. Conclusion: In above results, bond strength of titanium and low-fusing porcelain is influenced more to surface aspect than surface roughness. And titanium has clinically acceptable bond strength below surface roughness of $3.5{\mu}m$.

클록 보정회로를 가진 1V 1.6-GS/s 6-bit Flash ADC

김상훈,홍상근,이한열,박원기,이왕용,이성철,장영찬,Kim, Sang-Hun,Hong, Sang-Geun,Lee, Han-Yeol,Park, Won-Ki,Lee, Wang-Yong,Lee, Sung-Chul,Jang, Young-Chan 한국정보통신학회 2012 한국정보통신학회논문지 Vol.16 No.9

A 1V 1.6-GS/s 6-bit flash analog-to-digital converter (ADC) with a clock calibration circuit is proposed. A single track/hold circuit with a bootstrapped analog switch is used as an input stage with a supply voltage of 1V for the high speed operation. Two preamplifier-arrays and each comparator composed of two-stage are implemented for the reduction of analog noises and high speed operation. The clock calibration circuit in the proposed flash ADC improves the dynamic performance of the entire flash ADC by optimizing the duty cycle and phase of the clock. It adjusts the reset and evaluation time of the clock for the comparator by controlling the duty cycle of the clock. The proposed 1.6-GS/s 6-bit flash ADC is fabricated in a 1V 90nm 1-poly 9-metal CMOS process. The measured SNDR is 32.8 dB for a 800 MHz analog input signal. The measured DNL and INL are +0.38/-0.37 LSB, +0.64/-0.64 LSB, respectively. The power consumption and chip area are $800{\times}500{\mu}m2$ and 193.02mW. 클록 보정회로를 가진 1V 1.6-GS/s 6-비트 flash 아날로그-디지털 변환기 (ADC: analog-to-digital converter)가 제안된다. 1V의 저전압에서 고속 동작의 입력단을 위해 bootstrapped 아날로그 스위치를 사용하는 단일 track/hold 회로가 사용되며, 아날로그 노이즈의 감소와 고속의 동작을 위해 평균화 기법이 적용된 두 단의 프리앰프와 두 단의 비교기가 이용된다. 제안하는 flash ADC는 클록 보정회로에 의해 클록 duty cycle과 phase를 최적화함으로 flash ADC의 동적특성을 개선한다. 클록 보정 회로는 비교기를 위한 클록의 duty cycle을 제어하여 evaluation과 reset 시간을 최적화한다. 제안된 1.6-GS/s 6-비트 flash ADC는 1V 90nm의 1-poly 9-metal CMOS 공정에서 제작되었다. Nyquist sampling rate인 800 MHz의 아날로그 입력신호에 대해 측정된 SNDR은 32.8 dB이며, DNL과 INL은 각각 +0.38/-0.37 LSB, +0.64/-0.64 LSB이다. 구현된 flash ADC의 면적과 전력소모는 각각 $800{\times}500{\mu}m2$와 193.02 mW 이다.

Repression of TNF-α-induced IL-8 expression by the glucocorticoid receptor-β involves inhibition of histone H4 acetylation

김상훈,Doh-Hyung Kim,Paul Lavender,Ji-Hee Seo,Yun-Seop Kim,Jae-Suk Park,Sahng-June Kwak,Young-Koo Jee 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.5

Increased expression of a number of proinflammatory genes, including IL-8, is associated with inflammatory conditions such as asthma. Glucocorticoid receptor (GR)β, one of the GR isoforms, has been suggested to be upregulated in asthma associated with glucocorticoid insensitivity and to work as a dominant negative inhibitor of wild type GRα. However, recent data suggest that GRβ is not a dominant negative inhibitor of GRα in the transrepressive process and has its own functional role. We investigated the functional role of GRβ expression in the suppressive effect of glucocorticoids on tumor necrosis factor (TNF)-α-induced IL-8 release in an airway epithelial cell line. GRβ expression was induced by treatment of epithelial cells with either dexamethasone or TNF-α. GRβ was able to inhibit glucocorticoid-induced transcriptional activation mediated by binding to glucocorticoid response elements (GREs). The suppressive effect of dexamethasone on TNF-α-induced IL-8 transcription was not affected by GRβ overexpression, rather GRβ had its own weak suppressive activity on TNF-α-induced IL-8 expression. Overall histone deacetylase activity and histone acetyltransferase activity were not changed by GRβ overexpression, but TNF-α-induced histone H4 acetylation at the IL-8 promoter was decreased with GRβ overexpression. This study suggests that GRβ overexpression does not affect glucocorticoid- induced suppression of IL-8 expression in airway epithelial cells and GRβ induces its own histone deacetylase activity around IL-8 promoter site. Increased expression of a number of proinflammatory genes, including IL-8, is associated with inflammatory conditions such as asthma. Glucocorticoid receptor (GR)β, one of the GR isoforms, has been suggested to be upregulated in asthma associated with glucocorticoid insensitivity and to work as a dominant negative inhibitor of wild type GRα. However, recent data suggest that GRβ is not a dominant negative inhibitor of GRα in the transrepressive process and has its own functional role. We investigated the functional role of GRβ expression in the suppressive effect of glucocorticoids on tumor necrosis factor (TNF)-α-induced IL-8 release in an airway epithelial cell line. GRβ expression was induced by treatment of epithelial cells with either dexamethasone or TNF-α. GRβ was able to inhibit glucocorticoid-induced transcriptional activation mediated by binding to glucocorticoid response elements (GREs). The suppressive effect of dexamethasone on TNF-α-induced IL-8 transcription was not affected by GRβ overexpression, rather GRβ had its own weak suppressive activity on TNF-α-induced IL-8 expression. Overall histone deacetylase activity and histone acetyltransferase activity were not changed by GRβ overexpression, but TNF-α-induced histone H4 acetylation at the IL-8 promoter was decreased with GRβ overexpression. This study suggests that GRβ overexpression does not affect glucocorticoid- induced suppression of IL-8 expression in airway epithelial cells and GRβ induces its own histone deacetylase activity around IL-8 promoter site.

고등학교(高等學校) 재학생(在學生)들의 비합리적(非合理的) 신념(信念)과 정신병리(精神病理)

김상훈,최훈동,김학렬,Kim, Sang-Hoon,Choi, Hoon-Dong,Kim, Hack-Ryul 한국정신신체의학회 1995 정신신체의학 Vol.3 No.1

The purpose of this study is to investigate the relationship between irrational belief and psychopathology. The Korean version of Symptom Check List-90-R and Irrational Belief Test were administered to 621 high school students in group. The author used Pearson correlation coefficiency and multiple regression analysis to seek the regression patterns of the irrational belief. The results were as follows. 1) Most of the subscales of the SCL-90-R and Irrational Belief Test were correlated significantly. 2) In multiple regression analysis, the irrational belief associated with anxious overconcern was the most predictable variable for psychopathology.

고상반응법을 이용한 LAS계의 CaCO₃와 ZrO₂ 첨가에 따른 소결체 특성 연구

김상훈,강은태,김응수,황광택,조우석,Kim, Sang-Hun,Kang, Eun-Tae,Kim, Ung-Soo,Hwang, Kwang-Taek,Cho, Woo-Seok 한국결정성장학회 2011 한국결정성장학회지 Vol.21 No.5

저열팽창 특성을 갖는 난소결 물질인 LAS($Li_2O-Al_2O_3-SiO_2$)계를 고상 소결로 제조하였다. LAS계의 ${\beta}$-spodumene($Li_2O-Al_2O_3-4SiO_2$) 조성에 소결 조제로 $CaCO_3$를 첨가하였고, 강도 증가를 위하여 $ZrO_2$를 첨가하였다. 첨가제의 양의 변화와 소결 온도의 변화에 따른 소결 특성, 미세 구조, 기계적 특성 및 열팽창 특성에 대하여 조사하였다. 0.1 mol%의 $CaCO_3$을 첨가하였을 때, 치밀화가 증진됨을 미세구조 관찰에 의해 확인하였으며, $ZrO_2$의 첨가로 강도가 증진됨을 확인하였다. Dilatometer로 측정한 열팽창 계수는 선택된 전 조성에서 값이 $1.2{\sim}1.7{\times}10^6/^{\circ}C$임을 확인하였다. LAS ($Li_2O-Al_2O_3-SiO_2$) ceramics were sintered by a solid-state reaction. $CaCO_3$ and $ZrO_2$ were added to the ${\beta}$-spodumene ($Li_2O-Al_2O_3-4SiO_2$) composition of the LAS system for enhancement of sintering behavior and mechanical strength, respectively. We have investigated the sintering characteristics, microstructures, mechanical properties and thermal expansion characteristics according to the change of the amount of additive and sintering temperature of the ${\beta}$-spodumene. At 0.1 mol% $CaCO_3$, the densification of ${\beta}$-spodumene was significantly improved. At 0.04 mol% $ZrO_2$, the strength of ${\beta}$-spodumene was also improved. For all the selected all compositions, the thermal expansion coefficient was measured by a dilatometer, which revealed 1.2 to $1.7{\times}10^6/^{\circ}C$.

용접 열영향부 미세조직 및 재질 예측 모델링: V. 저합금강의 초기 오스테나이트 결정립크기 및 냉각 속도의 영향을 고려한 용접 열영향부 상변태 모델

김상훈,문준오,이윤기,정홍철,이창희,Kim, Sang-Hoon,Moon, Joon-Oh,Lee, Yoon-Ki,Jeong, Hong-Chul,Lee, Chang-Hee 대한용접접합학회 2010 대한용접·접합학회지 Vol.28 No.3

In this study, to predict the microstructure in weld HAZ of low alloyed steel, prediction model for the phase transformation considering the influence of prior austenite grain size and cooling rate was developed. For this study, six low alloyed steels were designed and the effect of alloying elements was also investigated. In order to develop the prediction model for ferrite transformation, isothermal ferrite transformation behaviors were analyzed by dilatometer system and 'Avrami equation' which was modified to consider the effect of prior austenite grain size. After that, model for ferrite phase transformation during continuous cooling was proposed based on the isothermal ferrite transformation model through applying the 'Additivity rule'. Also, start temperatures of ferrite transformation were predicted by $A_{r3}$ considering the cooling rate. CCT diagram was calculated through this model, these results were in good agreement with the experimental results. After ferrite transformation, bainite transformation was predicted using Esaka model which corresponded most closely to the experimental results among various models. The start temperatures of bainite transformation were determined using K. J. Lee model. Phase fraction of martensite was obtained according to phase fractions of ferrite and bainite.