융합성 망상 유두종증의 임상 및 병리조직학적 , 전자현미경적 고찰

이승헌,김균태,이원수,안성구 ( Seung Hun Lee,Kyun Tae Kim,Won Soo Lee,Sung Ku Ahn ) 대한피부과학회 1993 대한피부과학회지 Vol.31 No.6

표피지방(Epidermal lipid)과 표피장벽(Epidermal Barrier)

이승헌(Seung Hun Lee),장성남(Sung Nam Chang) 한국항공우주의학협회 1992 항공우주의학회지 Vol.2 No.2

사람피부의 해부학적 위치에 따른 피부장벽 손상후 회복율 및 피부표면 지질조성의 차이

이승헌 ( Seung Hun Lee ),구상완 ( Sang Wahn Koo ),황미선 ( Mee Seon Hwang ),이원주 ( Won Joo Lee ),김도원 ( Do Won Kim ) 대한피부과학회 1996 대한피부과학회지 Vol.34 No.1

Background: Lipids in the stratum corneum which acts as a barrier prevents transepidermal water loss and percutaneous absorption of a substance differs at different anatomic sites of skin. No study has yet been done on the recovery rate of the skin barrier after its destruction in relation to anatomic sites. Objectives : The purpose of this study was to measure the recovery rate of the skin barrier after its disruption in relation to anatomic sites and also to examine the lipid composition of skin surface lipids at different anatomic sites of skin. Methods : The study population consisted of 20 healthy male subjects. We used 3M Scotch tapes to remove the stratum corneum and examined the recovery rate by measuring the TEWL using an evaporimeter after 2.5, 6, 10, 24, 48 and 72 hours at eight different anatomic sites consisting of the post-auricular area, chest, abdomen, back, forearm, thigh and calf. The skin surface lipids were extracted using 99% ethanol at ten different anatomic sites including the face, chest, abdomen, back, upper arm, forearm, palm, thigh, shin and sole. The composition of skin surface lipids was determined by thin layer chromatography. Results : 1. The transepidermal water loss was highest in the post-auricular area and ahdomen, back, thigh, forearm, upper arm, thieh and chest in a decreasing order, although there was no statistical significance(p>0.05). 2. The recovery rate was highest in the post-auricular area after 2.5 hours with a statistical significance compared to other sites except for the abdomen(p<0.05). 3. The recovery rate was also highest in the post-auricular area after 6, 10, 24, 48 and 72hrs compared with other sites with a statistical significance (p<0.01). 4. Lipid analysis of ten anatomic sites demonstrated that the concentration of cholesterol sulfate was highest on the face, that of cholesterol was highest on the back and that of sphingolipid was highest on the abdomen but there was no statistical significance. Cpnclusion : The post-auricular area showed the fastest recovery rate after its barrier disruption which can be applied in the percutaneous absorption of substances. Also the composition of human skin surface lipids, especially epidermal lipids at different anatomic sites was not statistically different. (Kor J Dermatol 1996;34(1): 38-45)

신혈관성 고혈압 진단과 Captopril 검사

이승헌(Seoung Hun Lee),윤형규(Hyung Gue Yoon),송윤상(Yoon Sang Song),최문영(Moon Young Choi),김석은(Seok Eun Kim),박인석(In Seok Park),장윤식(Yoon Sik Chang),방병기(Byung Kee Bang) 대한내과학회 1994 대한내과학회지 Vol.46 No.1

N/A Background: The Captopril test (Muller, 1986) appears to represent a simple and useful screening tool in the diagnosis of renovascular hypertension. The limitations of the sennsitivity, specificity have been reported under certain circumstances. We performed this study to evaluate the sensitivity, specificity and predictive value of the Captopril test in the diagnosis of renovascular hypertension. Methods: We calculated the sensitivity, specicity and predictive value of the Captopril test in 26patients with clinical suspicion of renovasculr hypertension. We performed the Captopril test and renal angiography in these patients. Results; 1) The Captopril test was positive in 8 patients (30.7%), in whom 26renovascular hypertension were suspected. 2) The mean value of basal and stimulated plasma renin activity were 4.55±1.74ng/ml/hr and 19.89±7.19ng/ml/hr respectively, in 8patients with positive Captopril test. The mean value of percent increase of stimulated PRA was 384±227.9% in these patients. 3) The mean value of basal and stimulated plasma renin activity were 7.27±5.29ng/hr and 8. 78±5.89ng/ ml/hr respectively, in patients with negative Captopril test. The mean value of percent increase of stimulated PRA was 34.61±30.56% in these patients. 4) In patients with postivie Captopril test, there were 4true positive (50%) and 4false positive (50%) by renal angiography. In 18patients with negative Captopril test, there was 1false negative who had abnormal angiography. 5) The sensitivity, specificity and predictive value of the Captopril test were 80%, 81% and 50% respectively. Conclusion: The Captopril test seems to have limitations of sensitivity, specificity and predictive value in the diagnosis of renovascular hypertension. The careful clinical clinical application of Captopril test and renal angiography should be considered in the diagnosis of renovascular hypertension.

과학기술위성 2호 준비행모델 환경시험 결과

이승헌(Seung-Hun Lee),박종오(Jong-Oh Park),심은섭(Eun-Sup Sim),이승우(Seung-Woo Rhee),서정기(Jung-Ki Seo),장태성(Tae-Sung Jang),이상현(Sang-Hyun Lee),김성현(Sung-Hyun Kim) 한국항공우주연구원 2007 항공우주기술 Vol.6 No.1

과학기술위성 2호는 국내에서 최초로 개발되는 소형위성발사체(KSLV-1)에 의하여 국내 발사장(나로 우주센터)에서 발사될 위성이다. 2002년 개발을 시작하여 엔지니어링모델(EM), 준비행모델(PFM), 비행모델(FM)을 개발 완료하였다. 위성의 기능을 점검하기 위해 종합적인 전기/전자 기능시험과 우주환경시험, 발사환경시험을 수행한다. 본 논문은 성공적으로 수행한 과학기술위성 2호 준비행모델의 우주환경시험과 발사환경시험에 대한 분석과 그 결과를 보고한다. STSAT-2 (Science & Technology SATellite-2) is a Korea micro-satellite which will be launched at NARO Space center in Koheung, Korea. Launch vehicle for STSAT-2 is KSLV-1 (Korea Space Launch Vehicle-1) which is the first development in Korea space launch vehicle program. Starting development in 2002 EM(Engineering Model), PFM(Proto-Flight Model), and FM(Flight Model) were developed completely. Electrical functional test, space environmental test, and launch vehicle environmental test on system level are performed for testing those development models. In this paper we report the results of STSAT-2 PFM space environmental test and launch vehicle environmental test which is successfully completed.

표피장벽 손상 후 회복에 대한 이온영동 효과

이승헌 ( Seung Hun Lee ),강소군 ( Shaojun Jiang ),박태현 ( Tae Hyun Park ),최승호 ( Choong Bae Yoo ),안성구 ( Eung Ho Choi ),유총배 ( Sung Ku Ahn ) 대한피부과학회 1996 대한피부과학회지 Vol.34 No.3

Background: The stratum corneum(SC) has a permeability barrier function which regulates percutaneous absorption by the inhibition of transepidermal water loss(TEWL). Acute mechanical or chemical disruption of the SC induces the impairment of the permeability barrier and so increases the TEWL. The calciumtion has been recognized as an important ion in the recovery of the skin barrier. Recently the main delivery pathway of iontophoretic drugs have been suggested by SC interstices. However the morphologic changes in the SC interstices and calcium after iontophoresis have not been reported. Objective : The aim of our study is to confirm that iontophoresis may induce changes in the SC interstices and delay the recovery of the barrier after disruption. Material and Methods : After tape stripping the hairless mouse flank skin, the iontophoresis power supply (6V, 0.6mA) was connected to the patch atiached for 2.5 hours to the stripped site. We checked the THWL 0, 2.5, 6, 12, 18, 24 hours after the tape stripping and obtained specimens and performed osmium tetroxide, ruthenium tetroxide postfixation and calcium ion-capture cytochemical stains for electron microscopic study. Results : The recovery rate of the TEWL in iontophoresis was lower than in the control. This was especially so in the anouse which had received anode iontophoresis for 6 hours. It showed statistically lower TEWL than in the control(p<0.05). Anode iontophoresis induced low calcium in stratum granulosum (SG), but cathode iontophoresis induced high calcium in SC. After iontophoresis there were changes in the SC interstices structures. Conclusion : Iontophoresis can induce changes in the SC interstices and calcium distribution and so may help the topical drug delivery system. (Kor J Dermatol 1996;34(3): 375-380)

가변 저추력을 이용한 달탐사 임무궤도 설계

이승헌(Seung-Hun Lee),박종오(Jong-Oh Park),심은섭(Eun-Sup Sim),송영주(Young-joo Song),박상영(Sang-Yong Park) 한국항공우주연구원 2008 항공우주기술 Vol.7 No.1

제 2의 우주경쟁 시대를 맞이하여 세계 각국은 달을 선점하기 위한 치열한 경쟁을 벌이고 있다. 달에 영구기지를 2020년까지 건설하겠다는 미국을 비롯하여 유럽, 일본, 중국은 달탐사선을 성공적으로 발사하였으며 인도는 발사를 준비 중이다. 이와 같은 국제적인 분위기 속에 우리나라도 2020년까지 달에 탐사선을 보낼 계획을 발표하였다. 본 연구에서는 가변저추력을 이용한 달탐사 위성 설계에 기본 자료로 사용될 수 있는 달탐사 임무궤도를 설계하였으며, 이를 바탕으로 SMART-l과 비슷한 제원을 갖는 가상의 달탐사 임무를 설정하여 비행궤적을 산출하였다. Since the 1st space race between the United States and Soviet Union during the 1960s, we are competing 2nd space race to occupy the Lunar territory. Since the United States announced to construct the Lunar Base by the end of 2020, EU, Japan, and China launched Lunar explorers successfully. Even India is planning to launch a Lunar explorer in 2008. Korean government also announced that the Korea will launch first Lunar explorer in 2020. In this research Lunar mission trajectory design which will be fundamental data for Lunar mission with variable low thrust and Lunar mission trajectory which has a similar mission specification to SMART-1 are presented.

Hydrometer와 Corneometer를 이용한 피부표면 수분상태의 비교측정

이승헌(Seung Hun Lee),정준(Joon Chung),안성구(Sung Ku Ahn),강진수(Jin Soo Kang),권오규(Oh Kyu Kwon) 대한피부과학회 1994 대한피부과학회지 Vol.32 No.4

Background : Hydration, the water content of the stratum corneum, is an important factor in both the appearance and the barrier function of the skin. Many non-invasive methods have been developed in order to assesa the hydration state of the skin and the effect of various moisturizers. The hydrometer and carneometer are commercially available instruments which are widely used in dermatologic research. Objective : Our purpose wa,s to compare the measuring usefulnes of both instruments on normal subjects with a wide range of hydration states of the hornylayer. Methods : We measured the conductance with the hydrometer and the capacitance with the corneometer in various hydrating eonditions and compared both insruments. Results : Conductance had a non linear correlation with capacita ice. Capacitance measured with the corneometer had a high sensitivity to moisture in a wide range of hydration levels. On the other hand, conductance guaged with the hydrometer showed a few sensitivity to moisture at a low level. When the hydretion level was measured after a moiturizer was added, 10 % urea cream showed a sharp increase by 256% in terms of conductanae, and H-base by 97.8%. Mineral oil decreased by 41.5% and petrolatum by 62% respectively. On the other hand, when measured in terms of capacitance under the same conditions as above, 38.9 increase in 10% urea cream, 19.3% increase in H-base, 20% decrease in mineral oil, and 43.5 % decrease in petrolatum were reported. Conductance showed a higher hygroscopicity and a lower water holding capacity than capacitance did. When the measurement of the moisture level iri virious parts of the human body is performed, the corneometer provided us with more stable alies than the hydrometer. While the hydrometer can not the available and appropriate under the condition of insulation, the corneometer can measure moisture levels even down at the depth of 250mm. When measured after the oily surface of the forehead was cleansed with soft tissue, conductance and capacitance revealed higher values of moisture levels than before the eleanin. However, there is no statistical significance in these values. Conclusion : The hydrometer is a more appropriate tool for the measurement of moisture at a high level, and the corneometer at a low moisture level. The hydrcmeter is a more sensitive method of measuring the increase and the decrease in the moisture level. (Kor J Dermatol 1994; 32(4): 599-608)

여드름 환자와 아토피 피부염 환자의 수분상태와 지질의 측정과 비교

이승헌(Seung Hun Lee),박태현(Tae Hyun Park),이융재(Yung Jae Lee),박상훈(Sang Hoon Park) 대한피부과학회 1995 대한피부과학회지 Vol.33 No.3

Background : Skin surtice lipids increase and decrease in tints with acne vulgaris and in patients with atopic dermatis, respectively. Notably, hydratior. in decreased in patients with atopic dermatitis. Clinically it is common for the two diseases to occur together. Objective : We would like to find out the rate, clinical cteristics, and hydration and lipid levels when acne vulgaris and atopic dermatitis concur. Methods : We classific the clinical levels and measured the hydration and lipid levels of the face and forearm area of patients with acne vulgaris, patients phatopic dermatitis, and patients with both diseases, who visited the Youngdong Severance Hospital. Results : 1) 13.8% (14/102) of patients with acne vulgaris had at, epidermatitis. 31.1% (14/45) of patients with atopic dermatitis had acne vulgaris. 2) Patients with acne vulgaris had increased lipid levels and normal hydration levels. 3) Patients with atopie dermatitis had decreased lipid and iylration levels. 4) Patients withoth cnevulgaris and atopic dermatitis a no severe grade of acne vulgaris, and showed decreased hydration but normal lipid levels. Conclusion : In patients with both arne vulgaris and atoic dermatitis, clinically acne vulgaris was not severe and hydation levels were lower than normal controls. (Kor J Dermatol 1995;33(3): 459-486)

최근 병원 내원 여드름 환자의 통계적 고찰

이승헌 ( Seung Hun Lee ),박태현 ( Tae Hyun Park ),강원형 ( Won Hyoung Kang ),황규광 ( Kyu Kwang Whang ),이창우 ( Chang Woo Lee ),성경제 ( Kyung Jeh Sung ),안성구 ( Sung Ku Ahn ),박장규 ( Jang Kyu Park ) 대한피부과학회 1996 대한피부과학회지 Vol.34 No.3

Background: Many patients with acne have little information about its cause, course, and treatment although it is one of the most common skin diseases seen at hospitals. Objective : We would like to find out what acne patients think about the etiology of acne, what factors affect its course their treatment methods before going to hospital, and the psychological impact of acne. Methods : We classified the clinical levels of acne patients who visited seven university hospitals for the first time. We distributed questionnaires to them and analysed the results statistically. Results : 1) Patients were classified,according to their level of clinical severity : mild type(45.0%), moderate type(46.2%), and seuere type(8.8%). 2) The mean age at onset was 15.7 in males and 16.7 in females. 3) 69.3% of patients experienced that psychological stress had aggravated acne. 4) 42.8% of patients experienced that certain foods had aggravated acne. 5) 66.8% of female patients experienced aggravation of acne after starting to wear make-up. 6) 25.1% of female patients complained of a flare-up 1-7 days premenstrually. Conclusion : Acne is affected by many different factors, but there seems to be an especially close relationship between acne and the psychological factors which influence social life. (Kor J Dermatol 1996;34(3): 386-393)