망막병증을 동반한 제2형 당뇨환자에서 vitamin E투여후 단핵구 manganese superoxide dismutase(Mn-SOD)의 활성도 변화

배현철,최성남,공병호,오연상,신순현 중앙대학교 의과대학 의과학연구소 1998 中央醫大誌 Vol.23 No.1

There are some evidences that oxidative stresses have some roles in initiation and progression of the diabetic complications. Superoxide dismutase (SOD) is an essential enzyme for the dismutation of superoxide(:O2^-) radicals, and the activity is changed in some pathologic conditions such as diabetes. The aim of this study was to evaluate the association of Mn-SOD activity and severity of diabetic retinopathy and to compare between before and aftertreatment with vitamin E. The Mn-SOD activities were measured in 75 patients with NIDDM(41 noretinopathy, 21 nonproliferative retinopathy, 13 proliferative retinopathy) by spectrophotometry. The Mn-SOD activity(U/mg protein) was significantly elevated in diabetes after vitamin E treatment. The severity of diabetic retinopathy appeared not be statistically significant. In diabetic patients, there were no correlation between the Mn/SOD activity and the various clinical and biochemical parameters.

신장이식 수술로 치험한 신원거대감소증 3례

배현철,김병길,김유선,박기일,정현주,최인준 대한신장학회 1997 춘계학술대회 초록집 Vol.1997 No.-

미생물 에폭사이드 가수분해효소 활성을 이용한 유기용매에서의 광학활성 para-Nitrostyrene Oxide 생산

배현철,김현숙,이수정,이은열,양승택,김희숙 한국생명과학회 2002 생명과학회지 Vol.12 No.4

방향족 에폭사이드 기질에 대한 입체선택적 가수분해 활성이 우수한 Aspergillus niger LK를 이용하여 광학활성 (S)-para-nitrostyrene oxide를 제조하였다. 수용액에서 기질 의 낮은 용해도를 극복하기 위하여 유기용매에서 광학분할 반응을 수행하였으며, 생촉매 활성 저하가 가장 적은 dodecane을 유기용매로 선정하였다. 반응온도 3$0^{\circ}C$ 및 최적 water content 2% (v/v)의 조건에서 약 10시간 정도의 반응을 통해 ee 값이 100 %인 광학적으로 순수한 (S)-para-nitrostyrene oxide를 37% 정도(이론수율 : 50 %)의 높은 수율로 얻을 수 있었다. Enantioselective resolution of racemic para-nitrostyrene oxide was investigated using epoxide hydrolase activity of Aspergillus niger LK for the production of optically pure (S)-para-nitrostyrene oxide. To overcome the poor solubility of the substrate, enantioselective hydrolysis in an organic solvent was attempted under optimized reaction conditions including reaction temperature and water content. (S)-para-Nitrostyrene oxide with high optical purity (> 99% ee) was obtained at 37% yield using fungal epoxide hydrolase-catalyzed enantioselective resolution.

폐에서 발생한 경화성 혈관종 증례 1예

배현철,이광재,최병휘,박인원,허성호 대한결핵 및 호흡기학회 1995 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.81 No.-

Study on the fabrication processing of high-purity, high-density alumina green body prepared by a hydrothermal method

배현철,이상진 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.3

Along with the recent increase in consumption of sapphire single crystals, the alumina green body of high-purity and highdensity is required. The current manufacturing process for high-purity alumina using the aluminum or aluminum alkoxide compounds as a starting material had difficulties in mass production accompanied by the expensive equipments with high maintenance costs. Compared to this method, the high-purity alumina can be produced using the aluminum hydroxide dissolved in a caustic soda (sodium hydroxide) solution, in large quantity, with low cost. The mixing solution is aged for a certain period of time and then small amount of adsorbent is applied to selectively remove impurities in the solution. Finally a high purity alumina can be made from the refined solution. The alumina powders obtained through this method can be compacted and fired without any organic binder for the production of high-purity and high-density alumina green body. In this study, parameters in the manufacturing process employing the aluminum hydroxide to produce high-purity alumina were explored. And property changes of the final products were examined by varying the forming and firing parameters.

Fine-Pitch Solder on Pad Process for Microbump Interconnection

배현철,이학선,최광성,엄용성 한국전자통신연구원 2013 ETRI Journal Vol.35 No.6

A cost-effective and simple solder on pad (SoP) process is proposed for a fine-pitch microbump interconnection. A novel solder bump maker (SBM) material is applied to form a 60-μm pitch SoP. SBM, which is composed of ternary Sn3.0Ag0.5Cu (SAC305) solder powder and a polymer resin, is a paste material used to perform a fine-pitch SoP through a screen printing method. By optimizing the volumetric ratio of the resin, deoxidizing agent, and SAC305 solder powder, the oxide layers on the solder powder and Cu pads are successfully removed during the bumping process without additional treatment or equipment. Test vehicles with a daisy chain pattern are fabricated to develop the fine-pitch SoP process and evaluate the fine-pitch interconnection. The fabricated Si chip has 6,724 bumps with a 45-μm diameter and 60-μm pitch. The chip is flip chip bonded with a Si substrate using an underfill material with fluxing features. Using the fluxing underfill material is advantageous since it eliminates the flux cleaning process and capillary flow process of the underfill. The optimized bonding process is validated through an electrical characterization of the daisy chain pattern. This work is the first report on a successful operation of a fine-pitch SoP and microbump interconnection using a screen printing process.

여러 임베디드 장치의 통합 관리를 위한 프레임워크 개발

배현철,김상욱 대한임베디드공학회 2006 대한임베디드공학회논문지 Vol.1 No.2

in this paper, we propose the integrated security management framework supporting the trust for the ubiquitous environments. The proposed framework provides the gathering and analysis of the security related information including the location of mobile device and then dynamically configures the security policy and adopts them. More specially, it supports the authentication and delegation service to support the trusted security management for the ubiquitous networks. This system also provides the visible management tools to give the convenient view for network administrator.

$^{99m}Tc-DMSA$ 스캔에서 일측성으로 동위원소 섭취가 안되는 환아들에 대한 임상적 고찰

배현철,김현영,김병길,한상원,Bae Hyun-Chul,Kim Hyun-Young,Kim Pyung-Kil,Han Sang-Won 대한소아신장학회 1997 Childhood kidney diseases Vol.1 No.1

목적 : DMSA스캔은 신장의 형태학적 질환의 진단에 유용한 방사선과적 검사이다. 본원에서 DMSA스캔을 시행한 환아중 일측성으로 동위원소 섭취가 안되는 환아를 대상으로 이들의 성별, 연령별 분포와 임상적 소견, 원인질환 및 동반질환을 분석하고 이에 대한 치료 및 예후를 알아보고자 하였다. 방법 : 1980년부터 1995년까지 16년간 본원에 내원하여 DMSA 스캔을 시행한 생후 1일부터 15세 환아중 일측성으로 신기능을 상실한 경우와 5% 이내로 매우 저하되어 있는 61명을 대상으로 이들의 성별, 연령별 분포와 내원하게 된 주소, 내원당시의 임상적 소견, 정맥내 신우조영술, 복부초음파, 배뇨성 방광요관조영술, 최종 진단명, 동반되어있는 반대편 신장 및 전신 질환, 내원당시의 혈액검사, 치료, 그리고 추적 관찰후의 결과 등에 대한 항목을 조사하고 상호 연관관계를 분석하였다. 결과 : 1) 대상 환아의 연령 분포는 평균 3.3세였으며, 특히 1세이하가 전체의 46%였고 성별 분포는 남녀 1.4:1의 비율로 남아가 많았다. 2) 내원하게된 주소는 산전초음파에서 신장 이상이 발견된 경우가 31.2%로 가장 많았으며, 다음으로 반복적 요로감염, 복부종괴 촉지, 육안적 혈뇨, 복통 순이였으며, 다른 질환의 평가중 우연히 신장 이상이 발견된 경우도 26.2%를 차지하였다. 3) 내원당시 임상적 소견은 발열, 농뇨 등의 요로감염 증상이 가장 많았고, 고혈압, 복부종괴 촉지, 육안적 혈뇨, 변비, 무증상, 현미경적 혈뇨 순이였다. 4) 비기능성 신장의 최종진단명은 다낭성 신이형성(multicystic dysplastic kidney)이 36.1%로 가장 많았고, 수신증, 신발육부전, 신형성부전 순이였다. 5) 비기능성 신장의 치료는 47.5%에서 수술적 치료를 시행받았고, 수술적 치료중 신적출술이 75.9%(전체의 36.1%)로 가장 많았으며 그외에는 근피적 방광루조성술, 요관방광문합술, 신적출 및 신이식 순이였고, 32.8%는 치료없이 추적관찰만 했던 환아들이였다. 6) 반대측 신장에 침범된 질환은 수신증이 90.5%로 가장 많았고 신형성부전, 신원거대감소증이 각각 1례였다. 7) 총 61명의 환아중 4명이 만성 신부전으로 이행하였는데 이들은 모두 반대편 신장에도 심한 병변이 동반되었던 경우였으며 그 외의 환아들은 비교적 예후가 좋았다. 결 론 : 신기능을 상실한 신장중 대부분은 선천적인 질환에 의한 경우였으며 양측성으로 침범된 경우 만성신부전으로 이행한 경우도 있었으나 편측으로 침범된 경우 예후가 좋은 편이였으며 양측성인 경우도 조기진단 후 수술 받은 경우 신기능이 잘 유지되었다. 본 연구를 통하여 주산기 신장 병변에 대한 평가는 중요하며, 출생후 민감도가 높은 검사방법으로 조기에 진단하고 처치하면 비교적 예후가 좋다는 것을 알 수 있었다. The DMSA scan is a useful radiologic study in diagnosis of morphologic and functional diseases of kidney. We evaluated the distribution of sex and age, clinical manifestations, diagnosis, combined diseases, treatment and prognosis of the 61 patients with non-functioning kidney(no isotope uptake or uptake below 5% in DMSA scan) who admitted in our hospital from 1980 to 1995. The proportion of patients under 1 year old age was 46%. Sex ratio was 1.4:1 with male predominance. Most diagnosis of non-functioning kidneys were congenital such as multicystic dysplastic kidney, hydronephrosis due to ureteropelvic junction obstruction, renal agenesis and renal hypoplasia. In order of frequency thirty one percent of them were previously detected on antenatal ultrasonogram. Treatment consisted of operation in 47.5%, mostly nephrectomy and 32.8% of patients were followed up at OPD base without definite treatment. The most common combined diseases was hydronephrosis, in 4patients who had both kidneys inveloved progressed to chronic renal failure, but the prognosis in most cases were good. It is important to evaluate renal diseases in perinatal periods, and we believe that highly sensitive diagnostic study contribute to early treatment plan and thus to good prognosis.

BWLL용 MMIC 증폭기의 설계 및 제작

배현철,윤용순,박현창,박형무,이진구 한국전자파학회 2002 한국전자파학회논문지 Vol.13 No.4

In this paper, we have designed and fabricated an BWLL MMIC amplifier using GaAs PHEMT devices. We have optimized power divider/combiner size for small size of MMIC amplifier Using 0.2 ${\mu}$m AIGaAs/lnGaAs/GaAs PHEMT devices, the two stave MMIC amplifier has demonstrated a S$_{21}$ gain of 8.7 ㏈ with input/output return losses of lower than -10 ㏈ at 26.7 GHz. The size of this chip is 4.11 ${\times}$ 2.66 $\textrm{mm}^2$. 본 논문에서는 전자선 묘화 장비를 이용하여 게이트 길이가 0.2 $\mu$m인 PHEMT를 제작하여 특성을 분석하고, 임피던스정합 및 바이어스 회로를 위한 수동소자 라이브러리를 작성하여 BWLL용 MMIC 증폭기를 설계 및 제작하였다. 제작된 2단 MMIC 증폭기는 26.7 GHz에서 8.7 ㏈의 소신호 이득 및 -10 ㏈ 이하의 입 .출력 반사 계수를 얻었다. 제작된 2단 MMIC 증폭기의 팁 크기는 4.11$\times$2.66 $\textrm{mm}^2$ 이다.

신장이식 수술로 치험한 Oligomeganephronia 3례

배현철,김지홍,김병길,김유선,박기일,정현주,최인준,Bae Hyun-Chul,Kim Ji-Hong,Kim Pyung-Kil,Kim Yoo-Seon,Park Ki-Il,Jeong Hyun-Ju,Choi In-Jun 대한소아신장학회 1997 Childhood kidney diseases Vol.1 No.2

Oligomeganephronia is a rare congenital form of bilateral renal hypoplasia histologically characterized by reduction in number and hypertrophy of nephrons. Clinically, this condition is presented in early infancy with vomiting, polyuria, polydipsia and dehydration. The problems are readily corrected, but slowly progressive renal failure follows accompanied by failure to thrive, short stature, and renal osteodystrophy. We experienced three cases of oligomeganephronia. Case 1. : A 3 2/12 years old female child was incidentally diagnosed as renal failure at age of 2 months when she was hospitalized due to pneumonia. She had open renal biopsy and was diagnosed as bilateral dysplastic kidney. On OPD follow-up, she progressed to end-stage renal failure (BUN/Cr 114/4.6 mg/dl) and had renal transplantation. The specimen was shrunk remarkably and light microscopy showed oligomeganephronia. Case 2. : A 14 8/12 years old female child with proteinuria was detected in an annual urine screening program for school children, she was diagnosed as renal failure (BUN/Cr 33.9/4.1 mg/dl), and had $5{\times}4{\times}3\;cm$ sized mass on abdominal CT scan. She had renal biopsy, and the specimen showed oligomeganephronia. She had hemodialysis for six months, and renal transplantation along with bilateral nephrectomy was performed. Case 3. : A 14 8/12 years old male child was diagnosed having chronic nephritis and chronic renal failure at 3 years old, progressed to end-stage renal failure (BUN/Cr 87/9.6 mg/dl) on OPD follow-up, and had a rephrectomy and renal transplantation. The biopsy specimen showed oligomeganephronic hypoplasia, secondary focal segmental glomerolosclerosis, and chronic interstitial nephritis. We report 3 cases of oligomeganephronia that progressed to end-stage renal failure and had successful renal transplantation with a brief review of related literatures.