부하순환 하에서 제V급 복합레진 수복물의 미세변연누출에 대한 재접착제의 효과에 관한 연구

윤연희,김영재,김정욱,장기택,이상훈,김종철,한세현 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

저점도의 레진을 복합레진 수복물 위에 도포하는 것은 미세누출방지와 변연 완전성(integrity) 유지를 위한 한 방법이다. 하지만 장기간 관찰하면, 수복물은 저작압에 의한 영향을 받게 되는데, 저점도의 레진으로 수복물 변연부를 재접착(rebonding)하였을 때 저작압에 의한 응력에 견디면서 계속하여 수복물에 긍정적인 영향을 주는지에 대한 연구는 미흡한 실정이다. 본 연구는 부하순환(load cycling) 하에서 제Ⅴ급 수복물의 미세변연누출에 대한 재접착제 (rebonding agent)의 효과를 알아보고자 하였다. 40개의 건전한 소구치의 협면에 제Ⅴ급 와동을 형성하고 제조사의 지시대로 광중합복합레진으로 수복하였다. 20개씩 무작위로 나누어 표면전색을 하지 않는 Ⅰ군과 표면을 산부식 후 재접착한 Ⅱ군으로 설정하였다. 열순환 후 각 군에서 10개씩의 하위군 (A군=No load cycling군, B군=Load cycling군)으로 나누어 이중 B군의 시편에 1 Hz의 속도로 수직력이 4-100까지 100,000회의 부하순환을 가하였다. methylene blue용액에 침윤시켜 변연의 미세누출릉도를 평가하여 다음과 같은 결과를 얻었다. 1. 교합변연에서는 재접착과 무관하게 유의한 차이가 없었다(ⅠA-ⅡA군, ⅠB-ⅡB군) (p>0.05). 2. 치은변연의 경우는 부하순환을 하지 않은 군의 경우 재접착을 한 군(ⅡA군)이 재접착을 하지 않은 군 (ⅠA군)에 비해 더 적은 미세누출결과를 보였다(p<0.05). 3. 치은 변연에서 부하순환을 시행한 군의 경우에는 재접착을 한 군(ⅡB군)과 재접착을 하지 않은 군 (ⅠB군)과 유의차가 없는 비슷한 미세누출의 결과를 보였다(p>0.05). One clinical technique recommended f3r improving marginal integrity is "rebonding" or application of unfilled resins to the surface of composite restoration. But continuously the restorations are affected with occlusal load. There is room for doubt that the rebonding agent has the positive effect on microleakage in spite of the stress generated by the occlusal load. This study determined the effect of rebonding on microleakage of Class Ⅴ resin composite restorations under load cycling. Class Ⅴ cavities were prepared on the buccal surface of 40 sound extracted premolars and restored with a hybrid light-cured resin composite according to manufacturers' directions. They wert randomly divided into two groups consisting of 20 samples a control(group Ⅰ), without surface sealing, and the other group (group Ⅱ) in which margins were etched and rebonded. After thermocycling, each of groups was divided into subgroups (group A, B), and load cycling(total 100,000 cycles with 4-100N load at a rate of 1 Hz) were applied on the group B. Assessment of microleakage utilized methylene blue dye penetration. The following results were obtained : 1. In the occlusal region, no significant difference was noted in the scores regardless of whether or not the rebonding agent was used (group ⅠA-ⅡA, ⅠB-ⅡB) (p>0.05). 2. In the cervical region, the control group with rebonding (group ⅡA) showed the better result than the group without rebonding (group ⅠA) (p<0.05). 3. In the cervical region, the rebonded group with load cycling(group ⅡB) showed similar results to the groupf·ithout rebonding(group ⅠB) and no significant difference was noted(p>0.05).

상악 측절치의 치내치에 대한 증례보고 : REPORT OF 2 CASES

윤석희,이재천,김영재,장기택,한세현,김종철 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

치내치(dens invaginatus)는 치아 발생 과정 중 경조직이 석회화되기 전에 법랑질 상피가 함입되어 생기는 치아 기형이다. 치내치는 함입된 정도에 따라다양한 형태학적 변이를 보이는데 이러한 기형은 미생물이 침입할 수 있는 통로가 될 수 있어 치수조직의 괴사와 치근단 농양 또는 치은 농양의 원인이 된다. 이러한 경우 근고나의 복잡한 해부학적 형태 때문에 근관 치료가 매우 어렵다. 본 증례는 상악 좌측 측절치의 동통을 주소로 내원한 두 명의 환아들에 관한 것이다. 첫 번째 증례는 수산화 칼슘제재를 이용한 근관치료를 시행하여 양호한 결과를 얻었고 두 번째 증례는 치아를 발거하였다. 발거된 치아는 미세전산화 단층촬영을 이용하여 해부학적 형태를 살펴보았기에 보고하는 바이다. Dens invaginatus is a malformation of tooth resulting from an infolding of the enamel epithelium during tooth development. This malformation shows a broad spectrum of morphologic variations. This invagination frequently allows the entry of irritants and microorganism, which usually lead to necrosis of the adjacent pulp tissue and then to periapical or periodontal abscess. Root canal treatment of such tooth is often difficult because of the unusual form and complicated pulpal space. This article reports 2 cases of dens invaginatus in maxillary lateral incisors. The first case was successfully treated with Ca(OH)₂. In the second case, involved tooth was extracted and this extracted tooth was observed using the micro-computed tomography.

Ferric sulfate를 이용한 유치치수절단술의 3년 후 임상평가

윤연희,장기택,한세현 大韓小兒齒科學會 2002 大韓小兒齒科學會誌 Vol.29 No.1

15.5% ferric sulfate solution을 이용하여 유치치수절단술을 시행한 유구치의 상태를 임상적, 방사선학적으로 평가를 하여 이를 20%로 희석한 formocresol로 치수절단술을 시행한 경우와 비교하였다. 1997년부터 1998년까지 서울대학교병원 소아치과에서 치료를 받은 건강한 환아를 대상으로 하였고, ferric sulfate를 이용한 치수절단술을 치료받은 30개의 치아와 20%로 희석한 formocresol로 치수절단술치료한 23개의 치아, 총 53개의 치아를 평균 34개월 후 follow-up하여 그 임상적, 방사선학적 상태를 조사하였다. ferric sulfate군의 전체적인 성공률은 80.0%이었고, formocresol군의 성공률은 81.0%이었다. 두 군의 결과 차이를 카이제곱검정의 통계방법으로 분석하였다. ferric sulfate군의 4개의 formocresol군의 4개의 차이가 외흡수를 보였고 근단부 치조골파괴는 ferric sulfate군의 3개와 formocresol군의 2개에서 보였다. ferric sulfate군과 formocresol군 사이의 성공률은 통계학적으로 유의한 차이를 보이지 않았다. The objective of this report is to assess clinically and radiographically the state of the primary molars pulpotomized with a 15.5% ferric sulfate solution. The subjects selected were healthy children treated at the pediatric dental clinic of the Seoul National University Hospital in Korea. Thirty teeth were pulpotomized with a ferric sulfate solution(FS). Another twenty-one teeth were pulpotomized with 20% dilute formocresol(FC). Clinical and radiographic data for the fifty-one primary molars were collected with a mean follow-up period of 34 months. The success rate for the FS group was 80.0%. The success rate for the FC group was 81.0%. The differences in the results between the two groups were analyzed statistically utilizing the chi square test. External root resorption was observed in four teeth of FS group and four of the FC group. Periapical bone destruction was observed in three of FS group and two of FC group. There were no significant statistical differences between the success rates for FS group and the FC group.

줄넘기 運動의 有ㆍ無酸素的 運動强度 역치수준 設定을 위한 硏究

盧成圭,윤재원,김두경,하명수,장세원,윤중현 江原大學校附設體育科學硏究所 1987 江原大學校附設體育科學硏究所論文集 Vol.- No.12

The purpose of this study was the level of Aerobic-Anaerobic exercise intensity according to Rope skipping frequency by the skipping type at different age group(Middle, Junior high school and collegean). Types of Rope skipping(Jump, Leap and Double jump) with 100 rounds per min(5min), 120 rounds per min (5min) and max round frequency were tested by 120 volunteer untrained men and women students (forty middle school, forty high school and forty collegean) form Oct. 10. 1987 to No V.5. 1987. The results are showed at the skip intensity of 120 rounds per min. was higher than that of 100 rounds per min. at all skipping types, and men students showed less HR than women students. From the testing result, Double Jump was Considered as Anaerobic Exercise, Tean Jump was determined the strongest Aerobic exercise, and Jump or Leap were moderate Aerobic exercise. Recommending round frequency per min from multiple regression were follows. ----------------------------------------------------------------------------- Type Age 15 18 21 duration Sex ----------------------------------------------------------------------------- Jump man 127☆ 147 167 5min woman 113 126 140 5min ----------------------------------------------------------------------------- D.Jump man 137 169 211 2min woman 126 155 183 2min _____________________________________________________________________________ ☆ Round numbers per min

Identification of Biomarkers of Sepsis-associated Acute Kidney Injury Using Metabolomics Amino Acids Profiling in Intensive Care Unit

( Se Hyun Kwak ),( Sunyoung Ahn ),( Seung Hyun Yong ),( Ah Young Leem ),( Su Hwan Lee ),( Sang Hoon Lee ),( Song Yee Kim ),( Kyung Soo Chung ),( Eun Young Kim ),( Ji Ye Jung ),( Young Ae Kang ),( Youn 대한결핵 및 호흡기학회 2020 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.128 No.-

Background Acute kidney injury (AKI) following sepsis has been known to be associated with increased mortality. Methods Sepsis or septic shock patients admitted to medical ICU were enrolled from June 2018 through May 2019 at Severance hospital. End stage renal disease patients on dialysis were excluded. We divided septic patients into those with and without AKI within 48hr after admission to the ICU (D0). Patients with septic AKI were subdivided into AKI recovery and non-recovery groups according to whether kidney injury recovered within 7 days of the initiating event. We collected the serum samples of patients on D0. We used liquid chromatography tandem mass spectrometry (LC-MS/MS) for the application of metabolomics to research, and analyzed the Results to evaluate potential biomarkers of septic AKI. Results Of the 91 patients, 42 had sepsis, and 49 had septic shock. 84 were included with a median age of 71.0 (IQR 60.9-80.2). Compared with non-AKI and recovery AKI group, non-recovery AKI group showed highest baseline creatine (2.9 vs 1.2 vs 0.8, p<0.001), CCI (4.5 vs 3.0 vs 2.0, p=0.002), SOFA (10.0 vs 8.0 vs 6.5, p<0.001), and APACHE II score (32.0 vs 30.5 vs 21.5, p=0.004). In-hospital (73.3% vs 15.0% vs 23.5%, p<0.001) and 90-day mortality (66.7% vs 20.0% vs 20.6%, p<0.001) were also highest in the non-recovery AKI group. As a result of metabolomics approach using LC-MS/MS, hydroxyproline (14.7 vs 11.3, p≤0.01) and kynurenine (6.6 vs 3.3, p≤0.01) concentration at D0 in non-recovery AKI group were significantly lower than in that in those in non-AKI group. The area under the curve for hydroxyproline and kynurenine for prediction of non-recovery AKI were 0.646 (95% CI 0.517-0.762) and 0.740 (95% CI 0.615-0.842), respectively. Conclusions Our Results suggest that hydroxyproline and kynurenine could be useful biomarkers for non-recovery AKI diagnosis in sepsis patients in ICU.

Hematological manifestations of human immunodeficiency virus infection and the effect of highly active anti-retroviral therapy on cytopenia

Se Youn Choi,Inho Kim,김남중,Seung-Ah Lee,Youn-Ak Choi,Ji-Yeon Bae,Ji Hyun Kwon,Pyoeng Gyun Choe,박완범,Sung-Soo Yoon,Seonyang Park,Byoung Kook Kim,Myoung-Don Oh 대한혈액학회 2011 Blood Research Vol.46 No.4

Background :The aim of this study is to investigate the hematological manifestations of human immunodeficiency virus (HIV) infection, the risk factors for cytopenia, and the effect of highly active anti-retroviral therapy (HAART) on cytopenia. Methods :Medical records of patients treated for HIV at the Seoul National University Hospital from January 2005 to March 2010 were retrospectively reviewed. To determine the impact of HIV itself, we excluded HIV patients who had other conditions that could have resulted in hematological manifestations. Multiple logistic regression analyses were performed to identify risk factors for cytopenia. Results :A total of 621 cases were investigated, and after exclusion, data of 472 patients were analyzed. The frequency of cytopenia was anemia, 3.0% (14/472); neutropenia, 10.0% (47/472); thrombocytopenia, 2.4% (12/472); lymphopenia, 25.7% (121/470); isolated cytopenia, 11.2% (53/472); and bicytopenia, 2.1% (10/472). The leading risk factor for cytopenia identified by multivariate logistic regression methods was AIDS status at initial presentation. After HAART, cytopenia was reversed in the majority of patients (thrombocytopenia, 100%; neutropenia, 91.1%; and anemia, 84.6%). Conclusion :This study isolated the impact of HIV infection alone on hematologic manifestations and confirmed that these changes were reversible by HAART. Control of the HIV infection will have the main role in the management of hematological manifestations of the virus.

Myeloid-Derived Suppressor Cells Mediate Inflammation Resolution in Humans and Mice with Autoimmune Uveoretinitis

Jeong, Hyun Jeong,Lee, Hyun Ju,Ko, Jung Hwa,Cho, Bum-Joo,Park, Se Yeon,Park, Jong Woo,Choi, Se Rang,Heo, Jang Won,Yoon, Sun-ok,Oh, Joo Youn American Association of Immunologists 2018 Journal of Immunology Vol. No.

<P>Resolution of inflammation is an active process that leads to tissue homeostasis and involves multiple cellular and molecular mechanisms. Myeloid-derived suppressor cells (MDSCs) have recently emerged as important cellular components in the resolution of inflammation because of their activities to suppress T cell activation. In this article, we show that HLA-DR<SUP>−</SUP>CD11b<SUP>+</SUP>CD33<SUP>+</SUP>CD14<SUP>+</SUP> human MDSCs and CD11b<SUP>+</SUP>Ly6G<SUP>−</SUP>Ly6C<SUP>+</SUP> mouse MDSCs markedly increased in patients and mice during and before the resolution phase of autoimmune uveoretinitis. CD11b<SUP>+</SUP>Ly6C<SUP>+</SUP> monocytes isolated from autoimmune uveoretinitis mice were able to suppress T cell proliferation in culture, and adoptive transfer of the cells accelerated the remission of autoimmune uveoretinitis in mice. Alternatively, depletion of CD11b<SUP>+</SUP>Ly6C<SUP>+</SUP> monocytes at the resolution phase, but not CD11b<SUP>+</SUP>Ly6G<SUP>+</SUP> granulocytes, exacerbated the disease. These findings collectively indicate that monocytic MDSCs serve as regulatory cells mediating the resolution of autoimmune uveoretinitis.</P>

형상기억합금 메쉬 와셔 절연계의 파이로 충격 및 진동 절연 시험

윤세현(Se-Hyun Youn),장영순(Young-Soon Jang),한재흥(Jae-Hung Han) 한국항공우주학회 2009 韓國航空宇宙學會誌 Vol.37 No.3

우주 발사체의 비행 중에 파이로 충격은 일반적으로 여러 단 분리, 페어링 분리, 그리고 위성 분리 시 화약을 이용한 분리 장치의 작동에 의해 발생하게 된다. 이러한 분리 이벤트 시 고주파 영역까지 큰 가속도가 유발되는 천이 진동 현상이 유발되어 위성 또는 발사체의 전자 장비가 비정상적인 기능을 보일 수 있다. 본 논문에서는 이러한 파이로 충격 절연을 위해 형상기억합금 소재를 적용하여 두 종류의 메쉬 와셔 절연계를 소개하였다. 한 종류는 형상기억합금의 의탄성 효과를 주로 이용하였고 다른 한 종류는 형상기억효과를 주로 이용하였다. 형상기억합금 절연계의 기본적인 하중-변위 선도를 파악하기 위해 압축 시험을 수행하였고 그 결과로 절연 가능성을 확인하였다 파이로 충격 절연 시험을 수행하여 형상기억합금 절연계의 절연 성능이 뛰어남을 확인하였으며 추가로 랜덤 진동 시험을 통해 각 절연계의 통특성을 살펴보았다. In general, pyroshock is generated from the actuation of separation devices for several stage, fairing, and satellite separation in the flight of a launch vehicle. During these events, transient vibration phenomenon called pyroshock, which shows large acceleration in the high frequency range, occurs and it can result in the malfunction of electronic components which is equipped inside the launch vehicle or satellite. In this paper, mesh washer isolators made out of SMA were introduced for the isolation of pyroshock. One type of isolator primarily used pseudoelastic characteristics of SMA and the other type of isolator used shape memory effect of SMA. For the study of basic load-displacement relationship of each SMA isolator, compressive loading tests were performed and the results showed the capability of the isolator itself. Pyroshock isolation tests were followed and verified the outstanding isolation performance of isolator. In addition, random vibration tests were also performed and checked the dynamic characteristics of each SMA isolator.

초기압축변위에 따른 형상기억합금 메쉬 와셔 절연계의 절연 성능 비교

윤세현(Youn, Se-Hyun),정호경(Jeong, Ho-Kyeong),한재흥(Han, Jae-Hung) 한국소음진동공학회 2011 한국소음진동공학회 논문집 Vol.21 No.2

Launch vehicles and satellites experience severe vibration and pyroshock during the flight phase. These severe dynamic loading could result in the malfunction of electric devices which equipped in the launch vehicle and satellite. In this paper, mesh washer isolators are applied to attenuate these severe shock and vibration and isolation performances are enhanced by applying pseudoelasitic SMA wire material. Through random vibration and ground pyroshock tests, outstanding isolation performances are studied. Especially, comparison of isolation performances due to the change of pre-compressive displacement of mesh washer itself are suggested and applicablity to the adaptive vibration control are confirmed.

와이어메쉬 절연계의 파이로 충격 절연 성능 시험

윤세현(Se-Hyun Youn),장영순(Young-Soon Jang),한재흥(Jae-Hung Han) 한국항공우주학회 2008 韓國航空宇宙學會誌 Vol.36 No.9

파이로 충격은 고주파 영역까지 큰 가속도가 유발되는 천이 진동 현상으로 발사체에서는 주로 화약에 의한 분리 장치의 작동에 의해 발생하게 된다. 일반적인 발사체의 경우 단 분리, 페어링 분리, 위성 분리 이벤트에서 파이로 충격이 발생하게 되는데 이에 의해 위성 또는 발사체의 전자 장비가 비정상적인 기능을 보이거나 작동 불능 상태가 될 수 있다. 본 논문에서는 이러한 파이로 충격의 절연을 위해 와이어메쉬 절연계를 소개하였고 동일 단면을 기준으로 밀도와 높이를 다르게 9종류를 제작하였다. 와이어메쉬 절연계의 전형적인 특성을 살펴보기 위해 기본적인 압축 시험을 수행하였고 더미 질량을 이용하여 파이로 충격 시험을 수행, 충격 절연 효과가 뛰어남을 검증하였다. Pyrotechnic shock or pyroshock is characterized as a transient vibration phenomenon which shows large acceleration and high frequency range up to 10㎑ during the operation of separation devices where explosives are used. During the flight of a launch vehicle, pyroshock is mainly generated at several events such as satellite separation, fairing separation and stage separation. In this paper, wiremesh isolators are introduced and several types of isolators are manufactured for the performance tests. For the investigation of typical characteristics of wiremesh isolators, compressive loading tests are basically performed and pyroshock tests are accomplished to confirm pyroshock isolation ability of each wiremesh isolator by using 4㎏ dummy mass.