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.

수복재료와 내가동연결장치가 IMZ 임프란트 보철물의 충격흡수효과에 미치는 영향

이수정,정찬목,전영찬,Lee, Su-Jeong,Chung, Chan-Mo,Jeon, Young-Chan 대한치과보철학회 1997 대한치과보철학회지 Vol.35 No.1

The purpose of this study was to evaluate the shock absorbing effect of 4 restorative materials and intramobile connector. The damping effect of four restorative materials used to veneer test crown rigidly connected to IMZ implant and subjected to an impact force was measured. These materials included a gold alloy(stabilor G) : a noble metal ceramic alloy(Degudent H) : porcelain(Duceram) : composite resin(Dentacolor). In addition, this study compared damping effect of same restoretive materials after using polyoxymethylene intramobile connector(POM IMC). The result of this study suggest that : In case of using metal IMC 1. Veneered composite resin(group IV) reduced the impact force by 75%, when compared to an equivalent thickness of porcelain(group III). Group IV reduced the impact force by 87% and 89%, respectively, when compared to Stabilor G(group I) and Degudent H(group II). 2. The impact force recorded was higher for the alloy with the higher elastic modulus.(Stabilor G, group I, Young's modulus 107 Gpa, versus Degudent H, Group II, Young's modulus 95 Gpa) 3. It took the longest time for composite resin veneered group(IV) to reach to peak force when compared group I, II, III. In case of using POM IMC 4. The mean impact force recorded were reduced by 79%(group I), 78%(group II), 69%(group III), 84%(group IV), respectively, when compared to using metal IMC. 5. The time required to reach the peak force were increased by 78%(group I, II) 87%(group III), 34%(group IV), respectively, when compared to using metal IMC>.

성별, 연령 및 생리주기에 따른 대장 통과시간의 변이

이상전,이두한,송영진,최재운,장이찬 대한대장항문학회 1995 Annals of Coloproctolgy Vol.11 No.1

탱커운임지수 예측을 위한 VARMAX 모형의 설정

전찬영 한국해운학회 1999 해운물류연구 Vol.28 No.-

Vector Autoregressive(VAR) model can be usefully applied to various kinds of multiple macroeconomic time series data due to its ability to analyze many variables simultaneously. In VAR model, it's possible to know the response of one variable to an impulse of another variable and the proportion of forecast error variance of one accounted by others. Thus, one would like to investigate the relationship between two variables in a higher dimensional system. Nevertheless, there are many previous questions to be solved in utilizing the dynamic properties of VAR process. Amongst them, overparameterization and absence of proper estimation method are the key problems to limit the widespread use of the model. In this paper, for forecast of tanker freight rates VARMAX model will be established to overcome the overparameterization and Hannan and Rissanen's 3-step estimation method (HR method), which has been applied to ARMAX modeling, will be generalized in order to obtain the efficient estimate for the parameters of VARMAX model.

강판의 내식성 향상을 위한 환경 친화형 표면처리 : 다중코팅에 의한 시너지 효과 Synergy Effect by Multicoating

전상익,박찬영,류진호,이원기 한국환경과학회 2005 한국환경과학회지 Vol.14 No.1

Because of the toxicity of hexavelant chromium ion, treatments of metallic surface with chromate compounds to retard corrosion are undesirable for safety control in industrial uses and protection of environment. In this study, we investigated several compounds such as inorganic. organic. and polymer materials in order to substitute the chromate conversion treatment on steel sheet. The corrosion property was investigated in a salt spray tester with 3.5 wt.% NaCl at 35℃. The results showed that the zirconium/silane/polymer triple coatings on the galvanized steel exhibited a significant retardation of corrosion. Although the multicoating system needs a cornplexed processing. we can confirm a possibility of development of a chromate-free chemical conversion treatment for galvanized steel sheet.

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.

구조용 세라믹재료의 피연삭성에 관한 연구

이종찬,강용구,이태원,전영길,하상백 金烏工科大學校 1998 論文集 Vol.19 No.-

Structural ceramics have been widely used in engineering parts. It, however, is very difficult to grind the ceramics with desired shape and dimensional accuracy because of their high hardness, strength, and brittleness. Grindability of structural ceramics are quite different as they have different mechanical and physical properties. This paper compares the grindability of structural ceramics such as Al₂O₃Si₃N₄and SiC. The grinding experiments include the measurement of grinding force, surface roughness. and SEM observation. The experimental results indicate that Si₃N₄consumes the highest specific grinding energy among the three kinds of ceramics. It was also found that there is no corelationship between grindability and surface roughness of ground surface.

가토의 요추간반에 대하여 오존을 이용한 화학적 용해술

김영수,전병찬,권기영 The Korean Neurosurgical Society 2003 Journal of Korean neurosurgical society Vol.34 No.6

2차원 가공정보의 DB구축을 통한 CAM시스템 개발에 관한 연구

손영지,박정보,김순경,전언찬 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.2

NC code has to be made after changing the drawing information to DXF file, the convertig file. When the information is changed, the converted file is made decrease the unnecessary time of rapid feed during working and the DATA capacity after arranging the information ordered irregularly. This CAM program can be increased decreased uncomfortableness in contrast to use of each system based AutoCAD it can be increased productivity, example decrease of create time and product time about information, construct database of DXF code. And it can be used easely for the beginner of the minor enterprises. The connection of operations and the use of GUI increase business efficiency.

삼출성 늑막액에서 양악성 감별지표로서 CEA, TPA, SCC Ag 측정의 의의

김경찬,김민수,김미정,권두영,한승범,전영준 啓明大學校 醫科大學 1998 계명의대학술지 Vol.17 No.4

상피 세포에서 기원한 대표적인 종양표지자인 carcinoembryonic antigen (이하 CEA로 약함)은 삼출성 늑막액 환자의 양악성 감별에 보고적으로 사용되고 있다. CEA 이외에 혈청에서 양악성감별의 보조적 지표로 알려진 tissue polypeptide antigen (이하 TPA로 약함)과 squamous cell carcinoma antigen (이하 SCC Ag으로 약함)을 혈청과 늑막에서 동시 측정하여 늑막삼출액의 악성 감별에 어느 정도의 임상적인 유용성이 있는지를 알아보기 위하여 이 연구를 시행하였다. 1997년 1월 1일부터 동년 8월 31일까지 계명대학교 동산의료원에 입원한 환자들 중 삼출성늑막액을 가진 61명을 대상으로 하여 혈청과 늑막액에서 CEA, TPA, SCC Ag의 수치를 방사면역법으로 측정하였다. 각각의 조양표지자들은 악성과 양성군으로 구분한 뒤 분석하였으며 악성군이 28례, 양성군이 33례이었다. 그리고 진단양성기준치를 설정한 뒤 종양표지자들의 특이도, 민감도를 산출하였고 상기 지표들을 종양표지자와 늑막액 세포검사르 조합한 경우에도 산출하여 비교 분석하였다. 혈청 CEA 와 TPA는 각각 7.0 ng/ml, 80.0 ng/ml, 늑막액 CEA와 TPA는 각각 50. ng/ml, 4700.0 ng/ml로 진단양성기준치를 설정하였을 때 특이도를 낮추지 않으면서 가장 높은 민감도를 보였다. 늑막액 세포검사와 동시에 혈청 TPA 도는 늑막액 CEA를 측정하였을 때 특이도는 떨어뜨리지 않으면서 민감도를 높이는 좋은 조합인 것으로 나타났으며 혈청 CEA 및 TPA수치를 늑막액 세포검사와 도시에 시행하였을 때 특이도를 떨어뜨리지 않으면서 가장 높은 민감도를 얻었다. 늑막액 세포검사가 음성인 경우에도 혈청 CEA와 TPA를 동시에 측정하여 높은 민감도와 특이도를 얻을 수 있었다. 따라서 CEA와 TPA는 늑막삼출액의 양악성 감별 진단 유용한 보조적 지표로서 사용할 수 있을 것으로 판단된다. Carcinoembryonic antigen(CEA), the most widely used tumor marker was measured in pleural fluid of patients with exudative pleural effusions in order to differentiate malignant from benign effusions. This study was performed to find out if there is any clinical utility in differential diagnosis of malignancy by measuring simultaneously CEA, tissue polypeptide antigen(TPA) and squamous cell carcinoma antigen(SCC Ag) in serum and pleural fluid. The study population was 61 patients with exudative pleural effusions who were admitted to Keimyung University Hospital from January 1 to August 31, 1997. Each CEA, TPA and SCC Ag level in serum and pleural fluid were measured using radioimmunoassay method. These patients were divided to malignant and benign group. Malignant group consists of 28 cases and benign group consists of 33 cases. And the sensitivity and specificity of each tumor marker was obtained using cut-off value and that combining tumor markers and pleural fluid cytology were also obtained and analyzed. When the cut-off value was applied to CEA and TPA in serum using 7.0 ng/ml and 80.0 ng/ml respectively, the highest sensitivity was obtained without specificity being lowered. The same result was obtained when the cut-off value was applied to CEA and TPA in pleural fluid using 5.0 ng/ml and 4700.0 ng/ml respectively. When CEA in pleural fluid or TPA in serum were measured in combining with pleural fluid cytology sensitivity was increased without decreasing specificity than measured in pleural fluid cytology alone. When CEA in serum and TPA in serum were measured in combining with pleural fluid cytology simultaneously, the highest sensitivity was produced without decreasing specificity than measured in any other combinations. In addition, when serum CEA and TPA in serum were measured in the negative group of pleural fluid cytology, high sensitivity and specificity were obtained. These data suggest that CEA and TPA can be used as useful tumor markers for the differential diagnosis of malignancy and benign condition in patients with exudative pleural effusions.