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

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.

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.

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.

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.

롤의 배열이 자동차용 강판의 두께편차 및 마멸에 미치는 영향

손영지,김순경,전언찬 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

Work roll wear in the cold rolling of mild steel strip is strongly affected by rolling materials, rolling conditions such as roll arrangement in the cold rolling mill and lubrication. The tests were performed to find the effects of roll arrangement in the cold rolling mill on the work roll wear under the same lubricating conditions. The obtained results are as follows : If the distance of cold rolling is about 60 km, the surface roughness of its was reduced by half(Ra 0.49μm) and Pc(peak count) also was decreased to 60 ea/cm. It is easier for CC(Continuous casting) to make a slip on rolling than IC(Ingot casting). It is due to surface mirror in which first residual product appears and iron powder included Al2O3 is sticked. Because bending degree of 4Hi-rolling mill is higher than 6Hi-rolling mill, the first surface mirror was occurred to its center-point which is loaded strongly. 6Hi-rolling mill shape-controlled by intermediate roll doesn't need the initial crown to work roll. Therefore, fatigue and wear would appear a little bit.

Cisapride가 금식기 담낭의 수축운동에 어떤 영향을 미치는가?

송영진,장이찬,윤효영,이상전 충북대학교 의과대학 충북대학교 의학연구소 1996 忠北醫大學術誌 Vol.6 No.1

Cisapride의 식사후 담낭의 수축운동에 대한 영향을 규명하고자 20-30대의 건강인 12명(남자 6명, 여자 6명)을 대상으로 placebo, cisapride 10㎎ 혹은 20㎎을 경구복용한 후 담낭체적의 변화를 초음파로 측정하여 다음과 같은 결과를 얻었다. Placebo를 복용한 군에서는 검사기간중 완만한 체적의 변동이 있었으나, cisapride를 복용한 후에는 담낭체적이 지속적으로 현저하게 증가되었다. 이러한 담낭체적의 증가는 placebo를 복용한 군과 비교해 볼 때, cisapride 10㎎을 복용한 군에서는 60분후부터, 20㎎을 복용한 군에서는 50분후부터 통계학적 유의성이 있었으며(p<0.05), 이러한 경향은 검사종료시까지 지속되었다. 그리고 최대체적은 cisapride 10㎎을 복용한 군에서는 120분후에 최초체적의 145%에, cisapride 20㎎을 복용한 군에서는 90분후에 최초체적의 162%에 도달하였다(Fig. 2). 한편 체적곡선 아래의 면적은 cisapride 10㎎을 복용한 군은 31325 ±2518, 20㎎을 복용한 군은 33355 ±4726로, placebo를 복용한 군(23510 ±2864)보다 유의하게 컸다(p<0.05) 이상의 결과에서 cisapride의 경구섭취는 금식기 담낭의 수축운동을 억제하는 이완효과가 있음을 알 수있었다. 그리고 이러한 담낭수축억제효과는 장기간 cisapride를 복용하는 환자에서 담석형성이 촉진되는 효과가 있을 수 있고, 반대로 담석존재시 선통 발작을 억제하거나 예방하는 효과가 있을 수도 있다는 것을 시사한다. Cisapride(C23H29CIFN304) is one of the well-known prokinetic agents. It operates upon whole gastrointestinal tract, from lower esophageal sphincter to anal sphincter, and holds the most promise for patients with colonic motility disorders. It is known to function as an indirect cholinergic stimulant through increased release of acetylcholine in the intramural plexuses. Unlike metoclopramide, it does not have the antidopaminergic effects on the central nervous system. But its effect on the biliary system is not clearly elucidated. This study was performed in 12 healthy volunteers, and focused on the change of gallbladder volume after cisapride ingestion during fasting period. With the interval of 2-4days, placebo, 10㎎ or 20㎎ of cisapride were given. Cisapride inhibited the contraction of gallbladder compared with placebo. The results suggest that cisapride can induces the possible cholelithiasis, but, on the other hand, it can be used as the possible spasmolytic agent in the gallstone disease.

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.