TiNi/Al6061 형상기억복합재료의 고온에서의 손상거동에 대한 AE 특성

이진경,박영철,구후택 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.1

금속복합재료(MMC) 내부에서의 강화재와 기지재사이의 열팽창계수의 차이에 의해 발생하는 인장잔류응력은 복합재료의 인장강도를 저하시키는 심각한 문제중의 하나이다. 따라서 본 연구에서는 TjNi/Al6061 형상기억복합재료내부의 인장잔류응력의 문제를 해결하기 위하여 강화재로써 TiNi 합금을 사용하였다. TiNi 합금은 형상기억효과를 이용하여 복합재료내부에 압축잔류응력을 발생시킴으로써 인장강도를 증가시키는 역할을 한다. 복합재료내부에 압축잔류응력을 발생시키기 위하여 예변형(pre-strain)을 가하였다. 본 연구에서는 예변형의 변화에 따른 압축잔류응력의 영향을 평가하였으며 AE 기법을 이용하여 고온에서의 복합재료의 미시적 손상거동과 예변형의 영향을 평가하였다. It has been known that tensile residual stresses occurring by the thermal expansion coefficient mismatch between fiber and matrix is a cause of the weak strength of metal matrix composites(MMCs). In order to solve this problem, TiNi alloy fiber was used as a reinforced material in TiNi/Al6061 shape memory alloy composite in this study. TiNi alloy fiber improves the tensile strength of the composite by causing compressive residual stress in matrix on the basis of its shape memory effect. Pre-strain was imposed to generate the compressive residual stresses inside the TiNi/Al6061 shape memory alloy composites. AE technique was used to quantify the microscopic damage behavior of the composite at high temperature. The effect of applied pre-strains on the AE behavior was also evaluated.

세포질내 정자주입법(ICSI)에 있어서 정자흡입 및 난자내 주입방법에 관한 연구

이택후,김항진,송건호,김대근,전상식,박윤규,서태광,전병균,류은경,이은숙,문진수,김광철 경북대학교 의학연구소 2000 경북대학교병원의학연구소논문집 Vol.4 No.1

Study on Method of Sperm Aspiration and Injection into an Oocyte in Intracytoplasmic Sperm Injection(ICSI) Immobilization of spermatozoa prior to intracytoplasmic sperm iniection(ICSI) sometimes results in crooked tail and this makes it difficult to aspirate sperm into an injection pipette tail first. Head-first sperm aspiration into an injection pipette avoid this problem due to the bigger size of the sperm head. The effect of head or tail-first sperm injection into an oocyte on fertilization cleavage, percentage of grade I embryos and development to blastocyst stage in ICSI program has been studied. A single living immobilized spermatozoa from oligoasthenozoospermic patient was injected into an oocyte head-first or tail-first according to the treatment. Eighteen hours after microinjection, oocytes ware inspected for survival and fertilization Fertilized oocytes with two pronuclei were cultured in 30μl drop of mHTF supplemented with 10% heat-inactivated follicular fluid(FF) at 37℃. On day 2. embryo transfer was performed with cleaved embryos. The remaining 2-8 cell stage embryos were co-cultured with BRL cells in mHTF + 10% FF for 72 hours and the developmental stage was observed. The data were analyzed by Analysis of Variance. A total of 164 oocytes from 36 cycles were assigned to earth treatment and ICSI was performed(88 head-first, tail-first). The rates of normal fertilization were 81.8% and 76.3% for head-first and tail-first, respectively. Of the fertilized oocytes, the percentage of cleaved embryos and the percentage of grade 1 embryo among cleaved embryos were 88.9% and 68.8%, 93.1% and 74.1% for head-first and tail-first, respectively. Of the 2-8 cell embryos cultured, 44.4%(16/36) and 50.0%(10/20) for head first and tail first, respectively developed to blastocyst stage. There were no differences in fertilization, cleavage, rates of grade 1 embryos, and development to blastocyst stage. In conclusion, head-first or tail-first sperm injection into an oocyte in ICSI program does not affect fertilization and subsequent embryo development to blastocyst stage in vitro.

Effects of Mutagenesis for Glycosylation Sites of Recombinant Human EPO During Production from Cultured CHO Cell

Lee, Hyun-Gi,Seong, Hwan-Hoo,Im, Seok-Ki,Chung, Hee-Kyoung,Lee, Poongyeon,Lee, Yeun-Kun,Min, Kwan-Sik,Chang, Won-Kyoung,Lee, Hoon-Taek 한국수정란이식학회 2002 한국수정란이식학회 학술대회 Vol.2002 No.1

Human eryhropoietin (EPO) is acidic glycoprotein hormone that plays key role in hematopoiesis by facilitating differentiation of erythrocyte and formation of hemoglobin (Hb) and is used for the treatment of anemia. Human EPO is consist of 166 amino acids which is modified by three N-glycosylations (24, 38, 83) and single O-glycosylation (126). N-glycosylation is reported to be related to the cellular secretion and activity of EPO. In this study, we examined effects of mutagenesis in glycosylation site of recombinat hEPO for the cellular secretion during production from cultured CHO cell. We produced rhEpo which was cloned by PCR from human liver cDNA (TaKaRa) in cultured CHO cell. Using supernatant of the culture, ELISA assay and western analysis were performed. To estimate biological activity, 20IU of rhuEpo was subcutaneously injected into four ICR mice. After 8 days, HCT level was increased average 13 per cent, RBC was increased ca. 2106//. In disease model Rat (anemia c-kit, WSRC-WS/WS), HCT was increased ca. 12%, RBC was increased ca. 1.6106//. These results suggests that rhEpo we produced has biological activity. To remove glycosylation site by substituting 24, 38, 83, and 126th asparagine (or serine) with glutamic acid, overlapping -extension site-directed mutagenesis was performed. To add novel glycosylation sites, 69, 105th leucine was mutated to asparagine. Mutant EPO construct was transfected into CHO cell. Supernatant of the cell culture was analyzed using ELISA assay with monoclonal anti-EPO antibody (Medac, Germany). Since, several reports for mutagenesis of glycosylation sites showed case-by-case results, we examined both transient expression and stable expression. Addition of novel glycosylation sites resulted no secretion while deletion mutants had little effect except some double deletion mutants (24/83 and 38/83) and triple mutant. We suggest that not single but combination of glycosyl group affect secretion of EPO.

Comparison between preoperative and postoperative concurrent chemoradiotherapy for rectal cancer: an institutional analysis

Lee, Jeong Won,Lee, Jong Hoon,Kim, Jun-Gi,Oh, Seong Taek,Chung, Hyuk Jun,Lee, Myung Ah,Chun, Hoo Geun,Jeong, Song Mi,Yoon, Sei Chul,Jang, Hong Seok The Korean Society for Radiation Oncology 2013 Radiation Oncology Journal Vol.31 No.3

Purpose: To evaluate the treatment outcomes of preoperative versus postoperative concurrent chemoradiotherapy (CRT) on locally advanced rectal cancer. Materials and Methods: Medical data of 114 patients with locally advanced rectal cancer treated with CRT preoperatively (54 patients) or postoperatively (60 patients) from June 2003 to April 2011 was analyzed retrospectively. 5-Fluorouracil (5-FU) or a precursor of 5-FU-based concurrent CRT (median, 50.4 Gy) and total mesorectal excision were conducted for all patients. The median follow-up duration was 43 months (range, 16 to 118 months). The primary end point was disease-free survival (DFS). The secondary end points were overall survival (OS), locoregional control, toxicity, and sphincter preservation rate. Results: The 5-year DFS rate was 72.1% and 48.6% for the preoperative and postoperative CRT group, respectively (p = 0.05, the univariate analysis; p = 0.10, the multivariate analysis). The 5-year OS rate was not significantly different between the groups (76.2% vs. 69.0%, p = 0.23). The 5-year locoregional control rate was 85.2% and 84.7% for the preoperative and postoperative CRT groups (p = 0.98). The sphincter preservation rate of low-lying tumor showed significant difference between both groups (58.1% vs. 25.0%, p = 0.02). Pathologic tumor and nodal down-classification occurred after the preoperative CRT (53.7% and 77.8%, both p < 0.001). Acute and chronic toxicities were not significantly different between both groups (p=0.10 and p = 0.62, respectively). Conclusion: The results confirm that preoperative CRT can be advantageous for improving down-classification rate and the sphincter preservation rate of low-lying tumor in rectal cancer.

XFEM을 이용한 실리콘 박막 크랙 해석

이후민(Hoo Min Lee),서상재(Sang Jae Seo),김민혁(Min Hyeok Kim),조수진(Soo Jin Jo),임장균(Jang Kyun Lim),김영진(Young Jin Kim),이택상(Taek Sang Lee),이병호(Byeong Ho Lee),김문기(Moon Ki Kim) 대한기계학회 2014 대한기계학회 춘추학술대회 Vol.2014 No.4-2

자궁내막증 병변에서의 Cytokine mRNA의 발현 양상

이택후(Taek Hoo Lee),김광수(Gwang Soo Kim),김일규(Il Gyu Kim),전상식(Sang Sik Chun),조영래(Young Lae Cho) 대한산부인과학회 1999 Obstetrics & Gynecology Science Vol.42 No.9

목적: 자궁내막증은 최근에 그 빈도가 급격하게 증가되고 있으나 아직까지 병인과 치료법이 확실하게 정립되지 못하고 있는 부인과 내분비의 대표적인 질환이다. 최근 들어서 자궁내막증 환자의 불임의 원인으로 cytokine이 밀접하게 관여됨이 밝혀지고 있고 자궁내막증의 병인으로 복강내로 역류된 월경혈에 의한 복강내의 국소적 염증에 대한 개체의 반응정도와 면역체계의 변화가 중요하게 인정되고 있으나 아직까지 정확한 기전은 밝혀져 있지 않기 때문에 이에 저자는 자궁내막증 환자의 복수 내에서의 cytokine의 정량측정과 골반내 자궁내막증 병변조직에서의 cytokine mRNA의 발현 양상을 조사하여 자궁내막증 환자의 병인분석을 시도하였다. 연구방법: 자궁내막증 진단을 받고 복강경 혹은 개복 수술을 받은 30명의 환자에서 총 60개의 자궁내막증 병변이라고 의심되는 조직을 채취하여 이를 RT-PCR법을 이용하여 Cytokine 유전자의 발현양상을 조사하였다. 또한 7례의 정상대조군과 23례의 자궁내막증 환자의 복수를 ELISA법을 이용하여 정량분석을 시도하였다. 결과: 자궁내막증 환자의 복수내에서 IL-6와 IL-10의 농도는 자궁내막증의 임상적 중증도에 따라서 의미있게 증가되어 있었으나 IFN-γ, TNF-α, IL-1β, 그리고 IL-5의 농도는 정상 대조군에 비해서 변화가 없었다. 모든 예의 심부 자궁내막증 병변조직과 표재성 자궁내막증 병변조직에서 IL-1β cytokine mRNA의 발현을 볼 수 있었다. IL-5와 IL-6은 표재성 병변 12개 중에서 각각 2개의 black lesion에서만 발현을 볼 수 있었으며 IL-10은 표재성 병변에서는 12개중 2개에서 그리고 심부성 병변에서는 8개중 1개의 조직에서만 발현되었다. IFN-γ는 표재성 병변에서는 전혀 발현이 없었으나 심부성 병변에서는 8개중 4개의 조직에서 발현이 되었으며 TNF-α는 표재성 병변에서는 red 및 black 병변에서 각각 1개의 조직에서만 발현이 되었으나 심부성 병변에서는 역시 8개중 4개의 조직에서 발현이 되었다. 결론: 표재성 병변이 골반강내에 착상하여 염증성 반응이 일어날 수 있는 원인이 제공되면 IL-1β 혹은 TNF-α같은 염증성 cytokine이 분비가 되며 이로 인해 생성되는 단핵세포의 chemotactic factor에 의해 대식세포의 증가와 활성화가 이루어지고 이어서 복강내에 IL-6 등의 cytokine이 증가되며 마지막으로 여러 가지 증가된 cytokine에 대한 반대 반응으로 IL-10이 증가됨을 추정할 수가 있겠으며 이러한 가정은 앞으로 cytokine을 이용한 치료적 응용의 기초적인 연구로서 중요한 의미를 제공할 수 있다고 하겠다. Objective: The pathogenesis of endometriosis is generally accepted that retrograde menstruation and alterations in the local pelvic immune environment. This study was performed to help elucidate what kind of role various cytokines might play in the pathogenesis of endometriosis. Method: Concentrations of peritoneal fluid cytokines were compared in 7 women with normal pelvic finding and 23 women with endometriosis by enzyme-linked immunosorbent assay(ELISA). The patterns of cytokine mRNA expression in 8 ovarian endometrioma and 12 superficial pelvic endometriosis lesions were investigated by reverse transcription-polymerase chain reaction(RT-PCR) amplification method. Result: Both IL-6 and IL-10 levels in peritoneal fluid specimens with endometriosis tended to be higher than normal. However, there were no significant differences between peritoneal fluid concentrations of IFN-γ, TNF-α, IL-1β, and IL-5 of women with and without endometriosis. The levels of IL-6 and IL-10 were significantly higher in peritoneal fluid of women with severe endometriosis compared to women with mild endometriosis. IL-1β mRNA was expressed in all of 8 deep and 12 superficial endometriosis lesions. IL-5 and IL-6 mRNA were expressed in only two black lesions respectively, however, both were not expressed in the all deep lesions. Expressions of IL-10 mRNA occurred in one red and one black lesion while this was expressed in only one of the deep lesions. TNF-α mRNA was expressed in one red and one black lesion of 12 superficial lesions compared with four of the deep lesions. There was the difference between kinds of increased cytokines in the peritoneal fluid and those of expressed cytokines in the endometriotic lesions of patients with endometriosis. Conclusion: This study supports the concept that local immunologic factors may be important in the pathogenesis and pathophysiology of endometriosis. The pattern of cytokine mRNA expression of endometriotic lesions would seem to indicate that proinflammatory cytokines such as IL-1β and TNF-α are responsible for the development or progression of endometriosis.

표면 개질화된 천연제올라이트의 수분 흡착 특성

이후주(Hoo Joo Lee),이후근(Hoo Kun Lee),박근일(Geun Il Park),노성기(Seung Gy Ro),최호석(Ho Suk Choi),이용택(Yong Taek Lee) 大韓環境工學會 1999 대한환경공학회지 Vol.21 No.4

세포질내 정자주입법(ICSI)에 있어서 정자흡입 및 난자내 주입방법에 관한 연구

이택후 ( Taek Hoo Lee ),김항진 ( Hang Jin Kim ),송건호 ( Gun Ho Song ),김대근 ( Dae Geun Kim ),전상식 ( Sang Sik Chun ),박윤규 ( Yoon Kyu Park ),서태광 ( Tae Kwang Suh ),전병균 ( Byeong Gyun Jeon ),류은경 ( Eun Kyung Ryu ),이은숙 대한산부인과학회 1997 Obstetrics & Gynecology Science Vol.40 No.12

Immobilization of spermatozoa prior to intracytoplasmic sperm injection(ICSI) sometimes results in crooked tail and this makes it difficult to aspirate sperm into an injection pipette tail first Head-first sperm aspiration into an injection pipette avoid this problem due to the bigger size of the sperm head. The effect of head or tail-first sperm injection into an oocyte on fertilization, cleavage, percentage of grade 1 embryos and development to blastocyst stage in ICSI program has been studied. A single living immobilized spermatozoa from oligoasthenozoospermic patient was injected into an oocyte head-first or tail-first according to the treatment. Eighteen hours after microinjection, oocytes were inspected for survival and fertilization Fertilized oocytes with two pronuclei were cultured in 30 μ I drop of mHTF supplemented with 10 % heat-inactivated follicular fluid(FF) at 37℃. On day 2, embryo transfer was performed with cleaved embryos. The remaining 2-8 cell stage embryos were co-cultured with BRL cells in mHTF+10 % FF for 72 hours and the developmental stage was observed. The data were analyzed by Analysis of Variance. A total of 164 oocytes from 36 cycles were assigned to each treatment and ICSI was performed(88 head-first, 76 tail-first). The rates of normal fertilization were 81.8 % and 76.3% for head-first and tail-first, respectively. Of the fertilized oocytes, the percentage of cleaved embryos and the percentage of grade 1 embryo among cleaved embryos were 88.9 % and 68.8 %, 93.1 % and 74.1 % for head-first and tail-first, respectively. Of the 2-8 cell embryos cultured, 44.4 %(16/36) and 50.0%(10/20) for head first and tail first, respectively developed to blastocyst stage. There were no differences in fertilization, cleavage, rates of grade 1 embryos, and development to blastocyst stage. In conclusion, head-first or tail-first sperm injection into an oocyte in ICSI program does not affect fertilization and subsequent embryo development to blastocyst stage in vitro.

Evaluation of hematologic parameters in adnexal torsion

( Subeen Lee ),( Jisun Lee ),( Mi Joo Kim ),( Hyung Jeong Lee ),( Yoon Hee Lee ),( Gun Oh Chong ),( Dae Gy Hong ),( Taek Hoo Lee ) 대한산부인과학회 2019 대한산부인과학회 학술대회 Vol.105 No.-

Objective: Adnexal torsion is a condition which requires urgent surgical intervention to preserve ovarian function. Preoperative diagnosis of adnexal torsion is difficult because the diagnosis depends on findings from imaging studies along with various clinical symptoms. This study aims to compare preoperative hematologic parameters in patients with adnexal torsion and ovarian cyst. Methods: This is a retrospective study of 70 patients who visited emergency medical center for abdominal pain and received emergency operation under impression of adnexal torsion. Patients were categorized according to operative findings as adnexal torsion (Group1) and ovarian cyst (Group 2). Clinical characteristics and preoperative hematological parameters including age, body mass index (BMI), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte (PLR), mean platelet volute (MPV) were compared the two groups. All statistical analyses were performed by using the IBM SPSS statistics ver. 20.0 (IBM Co., Armonk, NY, USA). Results: Out of 70 patients, a total of 29 patients were found to have adnexal torsion and a total of 41 patients had ovarian cyst without torsion. The median BMI for Group 1 was 23.37 (18-29.73) and 20.9 (16-30.9) for Group 2 (p = 0.005). Group 1 group showed Group 1 had a median NLR of 4.94 (0.64-27.4), PLR of 195.53 (18.37-821), and Group 2 had a median of NLR 3.53 (1.05-21.56), PLR of 143 (35-345). The median MPV was 7.8 (6.3-10.30) for Group 1 and 7.9 (6.7-11.8) for Group 2. Group 1 had a median PT of 11.2 (10.1-13.5), aPTT of 25.5 (1.24-37.5), and Group 2 had a median PT of 11.6 (10.4-13), aPTT of 27.8 (21.2-37.2). There were no statistical differences between the two groups in terms of hematological parameters. Conclusion: Hematological parameters were not significantly different between ovarian torsion and ovarian cyst group. Further study with higher number of patients is needed to evaluate the preoperative role of hematological parameters in diagnosis of ovarian torsion.

Effect of Foliar Sprays of CaCl₂ on the Quality and Storability of ‘Changhowon Hwangdo’ Peach

Joong Won Lee,Chang Hoo Lee,Joon Taek Jang,Ji Young Lee 한국원예학회 2010 한국원예학회 학술발표요지 Vol.2010 No.5