Elderly kidney transplant recipients have favorable outcomes but increased infection-related mortality

임정훈,Lee Ga Young,Jeon Yena,Jung Hee-Yeon,Choi Ji Young,CHO, JANG-HEE,Park Sun Hee,김용림,Kim Hyung-Kee,Huh Seung,유은상,Won Dong Il,Kim Chan-Duck 대한신장학회 2022 Kidney Research and Clinical Practice Vol.41 No.3

Background: The number of elderly patients with end-stage kidney disease has been increasing, but the outcomes of kidney transplants (KT) remain poorly understood in elderly patients. Therefore, we evaluated the clinical outcomes of elderly KT recipients and analyzed the impact of elderly donors. Methods: This retrospective cohort study included patients who underwent KT between 2000 and 2019. KT recipients were divided into four groups according to a combination of recipient and donor age (≥60 or <60 years); elderly recipients: old-to-old (n = 46) and young-to-old (n = 83); young recipients: old-to-young (n = 98) and young-to-young (n = 796). We compared the risks of mortality, graft failure, and acute rejection between groups using Cox regression analysis. Results: The incidence of delayed graft function, graft failure, and acute rejection was not different among groups. Annual mean tacrolimus trough level was not lower in elderly recipients than young recipients during 10-year follow-up. Mortality was significantly higher in elderly recipients (p = 0.001), particularly infection-related mortality (p < 0.001). In multivariable Cox regression analysis, old-toold and young-to-old groups had increased risk of mortality (adjusted hazard ratio [aHR], 2.89; 95% confidence interval [CI], 1.14– 7.32; p = 0.03; aHR, 3.06; 95% CI, 1.51–6.20; p = 0.002). However, graft failure and acute rejection risks were not increased in elderly recipients. Conclusion: In elderly recipients, graft survival and acute rejection-free survival were not inferior to those of young recipients. However, mortality, especially risk of infection-related death, was increased in elderly recipients. Thus, low immunosuppression intensity might help decrease mortality in elderly recipients.

The Efficacy and Safety of 4-n-butylresorcinol 0.1% Cream for the Treatment of Melasma: A Randomized Controlled Split-face Trial

( Sun Young Huh ),( Jung Won Shin ),( Jung Im Na ),( Chang Hun Huh ),( Sang Woong Youn ),( Kyoung Chan Park ) 대한피부과학회 2010 Annals of Dermatology Vol.22 No.1

Background: Melasma is a common acquired symmetrical hypermelanosis that occurs on sun-exposed areas, and it is frequently observed among women. Various treatment modalities have been tried, but none are completely satisfactory. 4-n-butylresorcinol, which is a resorcinol derivative that has an inhibitory effect on both tyrosinase and tyrosinase-related protein-1, was introduced in 1995 and it has received increasing attention as a new hypopigmenting agent. However, the hypopigmenting effect of 4-n-butylresorcinol in human subjects has only been shown in a few studies. Objective: The aim of this study was to investigate the hypopigmenting efficacy and safety of 4-n-butylresorcinol 0.1% cream for the treatment of melasma. Methods: Twenty patients with melasma were enrolled to this randomized, double-blind, vehicle-controlled, split-face comparative study. The patients were instructed to apply 4-n-butylresorcinol 0.1% cream or vehicle to each side of the face twice daily for 8 weeks. Mexameter measurements were performed along with photography at baseline, 4 weeks and 8 weeks. Adverse events were observed and recorded throughout the study. Results: All the patients completed the study. Mexameter measurements demonstrated that the melanin index of the treated side showed a significant decrease when compared with that of the vehicle-treated side after 4 weeks (p=0.006) and after 8 weeks (p<0.0005). All the adverse reactions were mild and transient. Conclusion: 4-n-butylresorcinol 0.1% cream showed rapid efficacy and it was well tolerated when used for the treatment of melasma. (Ann Dermatol 22(1) 21∼25, 2010)

Case Report : A Case of Epstein-Barr Virus-associated Hydroa Vacciniforme

Sun Young Huh,Mira Choi,Kwang Hyun Cho 대한피부과학회 2009 Annals of Dermatology Vol.21 No.2

Hydroa vacciniforme (HV) is a photosensitivity disorder characterized by recurrent necrotic vesiculopapules on sun-exposed areas, which heal spontaneously during adolescence. Recently, an association has been reported between latent Epstein-Barr virus (EBV) infection and atypical HV-like eruption and malignant potential. However, latent EBV infection has also been reported in the setting of typical HV. An 11-year-old girl presented with recurrent, scattered, discrete vesicular eruptions with scarring on the face and the extensor surfaces of both forearms. In-situ hybridization was carried out to detect latent EBV infection. Based on the clinical and histopathological findings, typical EBV-associated HV was suspected. (Ann Dermatol 21(2) 209~212, 2009)

GMT-360 Yoke의 최적설계에 관한 연구

허선철,박영철,이동화,이광영,박원조 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

In this study, it is peformed to optimize important design variables of 3 dimensional GMI-36 Yoke which has a complicated shape. The design variables are a long and a short axis of an ellipse and parameters of upper part of Yoke and outer diameter of lower part of Yoke and the constraints are maximum stress and displacement. The weight of Yoke is minimized using Subproblem Approximation Method. The result is that 3.8% of total weight is reduced through this optimization and the feasibility of design compared with that of conventional model can be verified..

금 합금 보철물의 교합면 삭제로 인한 임플란트-골 계면으로의 열전달에 관한 연구

조재영,강선녀,정창모,윤미정,허중보,전영찬 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.1

연구 목적: 임플란트-골 계면에서 발생하는 과도한 열은 골유착을 저해하여 임플란트의 실패를 유발한다. 이에 이번 연구에서는 임플란트 금 합금 보철물의 교합면 삭제시 임플란트-골 계면으로의 열전달 양상과 냉각 방식의 효율성을 알아 보고자 하였다. 연구 재료 및 방법: 온도 감지 장치 제작을 위하여 Internal cone 연결형태의 임플란트에 16개의K형 열전대를 부착하여 아크릴릭 레진에 포매하였다. 치과용 금 합금과 주조용 abutment를 사용하여 교합면에 3개의 요철을 가지는 시편을 10개 제작하였고, 연결 나사를 이용하여 임플란트와 연결한 뒤 온도 감지 장치를 37℃로 유지되는 수조에 위치시켰다. 저속 핸드피스와 green stone bur를 이용하여 30초 동안 보철물의 요철을 삭제하였는데, 무냉각군, 공기 냉각 군, 물 분사 냉각 군으로 나누어 요철을 삭제하였다. 보철물이 삭제 되는 동안 임플란트의 부위별로 온도가 0.05초 간격으로 기록되었고, 삭제를 멈춘 뒤에도 무 냉각 군의 경우 임계 온도인 47℃ 이하로 온도가 하강할 때까지, 공기 냉각군과 물 분사 냉각군의 경우 삭제 중단 후 30초 동안 추가로 온도를 기록하였다. 냉각 방식에 따른 임플란트-골 계면의 온도를 알아보고, 임플란트의 부위별 온도변화의 유의차를 알아보기 위하여 one-way ANOVA를 실시하였고, Turkey HSD 이용하여 95% 유의수준에서 사후 검증하였다. 결과: 무 냉각 군은 임플란트-골 계면의 온도가 47℃ 이상으로 상승하였으며, 임플란트의 경부에서 유의하게 높은 열이 측정되었다(P>.05). 공기냉각군과 물분사 냉각군은 임플란트-골 계면의 온도가 47℃ 이하로 유지되었다. 무 냉각 군에서 임플란트 경부의 온도가 47℃에 도달되는 데는 약 10.8 ± 1.5초가 소요되었다. 공기 냉각 군과 물 분사 냉각 군 사이에서는 임플란트-골 계면 온도의 유의차가 없었다(P>.05) 결론: 이상의 결과로부터 임플란트 금 합금 보철물의 교합면 삭제 시, 임플란트 주위 조직에 위해를 가할 수 있는 임계 온도 이상의 열이 발생했음을 알 수 있었으며, 냉각방식은 공기 냉각과 물 분사 냉각 모두 효과적이라고 생각된다. PURPOSE. The purpose of this study was to analyze temperature change along the implant-bone interface induced by grinding the occlusal surface of implant gold prosthesis and to compare the temperature generated by grinding of prosthesis with different cooling methods. MATERIALS AND METHODS. The experimental gold prostheses were fabricated with dental gold alloy and castable abutment. The prostheses had 3 cylindrical protrusions on the occlusal surface with 1mm in height. Temperature was measured using 16 thermocouple wires attached to the implant fixture surface and the fixture was embedded in an acrylic resin block inside the 37℃ water bath. Cylinders were grinded for a period of 30 second with a low-speed handpiece with green stone point. One cylindrical protrusion was grinded without cooling, the second one was grinded with air blow, and the third one was grinded with water-spray. RESULTS. The mean maximum temperature was measured more than 47℃ of the implant and the maximum temperature was measured at the cervical portion of the implant in the group without cooling. There was statistically significant difference between the group without cooling and the groups with cooling (P<.05). However, there was no significant difference at all portion of implant in the groups with cooling (P>.05). CONCLUSION. The results of this study support that the grinding of implant gold prosthesis without cooling may damage the peri-implant tissue. The continuous use of air blow and water-spray adjacent to prosthesis during the grinding of implant gold prosthesis may prove to be beneficial for cooling of the implant.

Mitsunobu 반응을 이용한 Ethyl 2-Fluoro-2-phenylsulfonylethanoate의 벤질화 반응

허선철,김대영 순천향대학교 기초과학연구소 1999 순천향자연과학연구 논문집 Vol.5 No.1

1-1'-(아조디카르보닐)-디피페리딘(ADDP)-트리부틸포스핀(TBP)을 이용한 Mitsunobu 반응을 통하여 에틸 2-플루오르-2-페닐술포닐에탄오에이트와 벤질알콜로부터 에틸 2-플루오르-3-페닐-2-페닐술포닐프로판오에이트를 비교적 높은 수율로 합성 하였다.

가축에서 분리된 Vancomycin 내성 장구균의 내성유전자 구조 분석을 통한 분자생물학적 역학 연구

허지영,이선민,이석호,이위교,용동은,이경원,신완식,이동건 대한임상미샐물학회 2003 Annals of clinical microbiology Vol.6 No.2

세라믹/금속접합재에 대한 접합계면의 응력특이장해석

박영철,허선철,윤두표,강재욱 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.1

Since the ceramic/metal joints at high temperature, the residual stress will develops during when it is cooled from bonding temperature due to remarkable difference of thermal expansion coefficient betwen ceramic and metal. Moreover, the edge of jointed interface makes singular stress field in the ceramic/metal joints and this singular stress field much influences on the strength of joints. In this study, the influence of residual stress, mechnical load and repeat thermal cycle were estimated in the ceramic/metal joints. According to this influence, the change of singular stress field was analyzed. The results are as follow : 1) Strength of joints was evaluated by the stress singularity index λ and the intensity K of singular stress field. 2) the stress singularity index λ and the intensity K of singular stress field also increase as adding temperature of thermal cycle and its number of cycle. 3) In the case of mechanical load, the influence of residual stress reduces since the difference(Δλ) of stress singular index between existence and inexistence of residual stress decreases in proportion to the increasing of tensile load.

MoSi_2기 복합재료의 소결온도에 따른 미끄럼마모 특성

이광영,박원조,허선철,김형진,박성호 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

Molybdenum disilicide(MoSi_2) is considered to be a promising high temperature material for turbojet anhypersonic engines in aerospace and various industrial applications, because of a high melting point(2030℃),adequate density(6.3g/cm^3) and an excellent oxidation resistance. Mosi2 powder was evaluated from the variation of fabricating such as preparation temperature 1250℃, 1350℃ and 1500℃ respectively. Abrasion tester used a pin-on-disk type and a Si3N4 ceramic ball which used as machine structural materials. The test condition apply to load of 8kgf at 7.5rpm for 6 hours and the effect of hardness is also discussed. As a result of the tests, the friction coefficient was decreased with sintered MoSi_2 of increasing temperature but the function coefficient did not vary much for all specimens at all temperatures.

FRONT SUSPENSION의 LOWER ARM에 대한 최적설계

박영철,윤두표,허선철,조용배 동아대학교 공과대학부설 생산기술연구소 1997 生産技術硏究所硏究論文集 Vol.2 No.1

LOWER ARM which jointed Independent Front Suspension is resulted in stress sidtribution analysis by using Finite Element Method. These datas represented in the condition of 8 loads and 3-type-section(I, H and H+I) type. On the basis of it, it is optimized shape and dimension fo LOWER ARM. The optimized performance shows that the H type of 3 types has an available strength and H´ section, which proved by H type, finds safety factor and yield strength in each case of load condition.