The effect of ginsenoside Rk1 in junctional protein of severe preeclamptic placenta

Objective: To investigate the differential expression of junctional proteins in the normal and preeclamptic human placenta and the effect of ginsenoside Rk1 in junctional proteins. Methods: Placental tissues from 10 women with severe preeclampsia and 5 normal women were collected at the time of their cesarean section. Five of 10 preeclamptic women were complicated with intrauterine growth restriction (IUGR). Immunohistochemistry and Western blotting was employed to localize junctional proteins (zo-1, occludin and plakoglobin) positive cells. The placental explant culture was performed to investigate if Rk1 can attenuate the expression of junctional proteins (zo-1, occluding and plakoglobin) induced by deferoxamine-induced hypoxia. Rk1 was treated at the day 3 and Western blot analysis was performed for protein quantification. Results: There was no different expression of zo-1 and plakoglobin among all the study groups. Occludin showed negative at the endothelial cells of the terminal villi in both normal and preeclampsia groups. At the endothelial cells of the stem villi, occludin was detected in both normal and severe preeclamptic placenta with normal fetal growth. However, severe preeclampsia with IUGR were decreased expression of occludin at the endothelial cells of the stem villi. When we administered Rk1 to the placenta treated with DFO, expression of occluding was not different. Conclusion: The placental expression of zo-1 and plakoglobin were not different among the study groups, while that of occludin was significantly decreased at the endothelium of stem villi in severe preeclampsia with IUGR. Rk-1 showed no effect on the placental junctional proteins. These results suggest that occludin may play a role in pathophysiology of fetal growth restriction in uteroope

First Trimester Placental Volume and Second Trimester Uterine Artery Doppler Velocimetry in the Prediction of Perinatal Outcomes

Objective: To determine to what extent the placental quotient (PQ: placental volume/crown-rump length) is able to detect adverse perinatal outcomes and to compare the value of first trimester placental volume and second trimester uterine artery Doppler velocimetry for predicting adverse perinatal outcomes. Methods: This was a prospective study comprising of 263 women with singleton pregnancies attending our hospital for nuchal translucency screening at 10-13 weeks of gestation. Three dimensional ultrasound was used to obtain images for measurement of placenta volume at 10-13 weeks of gestation. In addition, Doppler assessment of both uterine arteries was carried out for measurement of the pulsatility index (PI) in the second trimester and the mean PI of the two vessels was calculated. The variables of adverse perinatal outcomes were preeclampsia, preterm delivery, small for gestational age (SGA), 5-minute APGAR score, and admission to the neonatal intensive care unit. Results: Of the initial 263 pregnancies originally participating, 219 women who delivered at our institution were included in the final analysis. Pregnancy complications occurred in 27 (12.3%) of the 219 pregnancies. Comparison between crownrump length and placental volume proved a significant correlation (r=0.474, p<0.001). There were no correlation between PQ and uterine artery Doppler velocimetry PI. PQ was significantly lower in SGA group and neonatal intensive care unit admission group (p=0.049, p=0.019, respectively). Uterine artery Doppler velocimetry PI was significantly higher in SGA group (p=0.024). PQ in the first trimester and uterine artery Doppler velocimetry in the second trimester had similar sensitivities for predicting SGA. Conclusions: PQ in the first trimester and uterine artery Doppler velocimetry PI in the second trimester have significant difference in SGA group compared to appropriate for gestational age, and have similar sensitivities for predicting SGA. While both methods seem to be insufficient for screening, the PQ method has the potential advantage of being performed in the first trimesterope

Prediction of severe preeclampsia with routine antenatal care and uterine artery doppler velocimetry

의학과/석사[한글]목적: 정기적 산전검사에서 얻을 수 있는 정보를 통하여 중증 전자간증의 발생과 관련 있는 인자를 파악하고 이 요인들의 상대 위험도를 평가하여 중증 전자간증 발생 예측의 유용성을 평가한다. 연구방법: 2003년 1월부터 2007년 12월까지 연세의료원 세브란스병원에서 임신 제1삼분기부터 정기적인 산전진찰을 받고 분만한 876명의 단태임신 산모를 대상으로 환자의 의무기록, 진단검사의학적 검사 결과 그리고 초음파검사 결과를 후향적으로 분석하였다. 내과적 질환, 다태임신, 전자간증 이외의 산과적 합병증이 있는 환자는 제외하였고 태아기형이 확인된 경우도 제외하였다. 산과력, 임신 제1삼분기의 혈청화학적 검사, 임신 제2삼분기의 기형아 선별을 위한 삼중표지자검사, 임신 제2삼분기의 자궁동맥 도플러 혈류 검사의 자료를 분석하였다. 결과: 876명의 산모 중에서 38명이 중증 전자간증으로 진단되었다 (4.3%). 정상군과 중증 전자간증군사이에서 일변량 분석을 통하여 산모의 나이, 체질량지수, 중심동맥압, 산모혈청의 화학적검사(BUN, 크리아티닌, 요산), 삼중 표지자 검사 중 알파태아단백, 사람융모생식샘자극호르몬 그리고 자궁동맥 도플러 검사가 의미있는 차이를 보였다. 이들 위험인자를 로지스틱 회귀분석을 시행하였다. 이전 임신에서의 전자간증 발생의 기왕력이 가장 높은 위험도를 보였다 (OR 67.0, 95% CI 18.8-238.3). 다음으로 비정상 자궁동맥 도플러(OR 7.9, 95% CI 2.8-22.4), 알파태아단백(OR 6.8, 95% CI 1.9-24.6), 사람융모생식샘자극호르몬(OR 3.0, 95% CI 1.3-7.0)의 순서였다. 체질량지수와 평균동맥압 그리고 요산의 증가도 중증 전자간증의 발생에 있어 위험인자로 작용하였다. 결론: 정기 산전검사에서 전자간증의 기왕력이 가장 높은 위험도를 보였다. 비정상 자궁동맥 도플러 혈류 검사와 기형아 선별을 위한 삼중표지자 검사 중 알파태아단백, 사람융모생식샘자극호르몬의 증가는 중증 전자간증을 예측하는 지표로 사용될 수 있다. 이와 더불어 체질량지수의 증가, 평균동맥압의 상승, 혈중 요산의 증가가 중증 전자간증 예측 인자가 될 수 있다. [영문]Objective: To determine the risk factors and relative risk for preeclampsia from data obtained through routine antenatal care Methods: The study group consisted of 876 pregnant women who received continuous routine antenatal care and delivered at Yonsei University Health System from Jan. 2003 to Dec. 2007. We retrospectively reviewed the medical records, laboratory data and ultrasonographic findings. Pregnancies with multiple gestation, congenital anomaly, and abnormal placentation were excluded. Statistical analysis was carried out by chi-square, t-test and logistic regression by SPSS (ver. 14.0). Results: Thirty eight women were diagnosed with severe preeclampsia among the 876 women in the study group. Age, body mass index (BMI), mean arterial pressure, maternal serum chemistry (BUN, creatinine and uric acid),13 AFP, hCG, and abnormal artery Doppler velocimetry were significantly different between the preeclamtic group and normal group according to the univariate analysis. Logistic regression was performed to evaluate risk factors for severe preeclampsia. Prior history of preeclampsia was the strongest risk factor (OR 67.0, 95% CI 18.8-238.3). Abnormal uterine artery Doppler was the second highest risk factor (OR 7.9, 95% CI 2.8-22.4) followed by AFP(OR 6.8, 95% CI 1.9-24.6) and hCG (OR 3.0, 95% CI 1.3-7.0). BMI and mean arterial pressure were risk factors for severe preeclapmsia Conclusion: Elevated level of AFP, hCG and abnormal uterine artery Doppler velocimetry could be used as risk factors for severe preeclampsia. BMI and MAP were also significant risk factors. Overall, the most powerful risk factors for preeclampsia was prior history of preeclampsia in multiparity.ope

(A) clinical study of the meningioma

의학과/석사[한글] 두개강내 양성종양중 가장 발생빈도가 높은 것으로 알려져 있는 뇌수막종의 진단 및 치료방법의 개선에 도움이 되고자, 1966년 11월부터 1982년 10월까지 본 연세의료원 신경외과에서 뇌수막종으로 수술받은 총 94명의 환자를 대상으로 병상일지를 근거로한 임상분석을 하였던 바 다음과 같은 결과를 얻었다. 1. 뇌수막종 환자의 연령은 30대와 40대에 가장 많이 분포하여 각각 전체의 30.8%을 씩을 차지하였으며, 성별빈도는 1:1.4로 여자에 다소 많았다. 2. 뇌수막종의 발생부위로는 부상시상동 및 대뇌겸부위가 전체의 37.2.%를 차지하였으며 그 다음이 접형골연( 15.9%), 궁륭부( 14.9%), 안배상부 (10.6% 1) 순이었고, 1979년 세계보건기구가 권장하는 병리조직학적 분류에 따르면, meningotheliomatous형이 전체의 64.9%로 가장 많았으며, 저악성 혹은 악성인 hemangiob1astio, hemangioprioytic, papillary 및 anaplastic형이 모두 9예로 전체의 9.6%에 달하였다. 3. 임상증상은 두통 (55.5%), 시력장애 (17.0%1, 전간 (14.9%) 등의 순이었고, 방사선학적 소견상 단순두개골촬영에서는 반수이상에서 이상소견을 보였다. 뇌전산화단층촬영은 가장 정확하고 안전하게 시행할 수 있는 방법이었고, 뇌혈관조영술로 종양에 분포하는 혈관의 양상이외에도 유출정맥 및 정맥동과의 관계를 알아볼 수 있었다. 4. 뇌기저부 뇌수막종에 해당되는 14예중 6예는 완전제거 되었으나 8예에서 종앙의 부분적출만이 가능하였고 수술후 증세악화가 3예, 사망이 2예로 경과는 매우 나빴다. 5. 재발된 8예중 1예를 제외한 나머지는 모두 부상시상동부위에 위치한 경우였으며, 병리조직학적으로는 hemangiopericytic형 3예, hemangioblastic형 2예, angiomatous형 2예 및 meningitheliomatous형 1예였다. 6. 총 4예에서 수술시 laser를 사용하였던 바 출혈과 주위 정상뇌조직의 손상을 줄일 수 있었고 수술후 뇌부종을 극소화시킬 수 있었다. [영문] To Provide a guideline of accurate diagnosis and proper methods of treatment of meningioma, the most common benign intracraninal tumor, the author studied 94 cases of intra & extracranial meningioma who had been diagnosed and operated at the Department of Neurosurgery of Yonsei University of medicine from November 1966 to October 1982. The results were as followings . 1. The ratio of male to female was 1 to 1.4 and 30.8% of the 94 patients was in the 4th decade of age and another 30.8% in the 5th decade. 2. The predilection states were parasagittal and falx (37.2%), sphenoid ridge (15.9%), convexity(14.9%), and suprasellar(10.6%) area. According to W.H.0. classification (1979), the most common histopathological type was menlngotheliomatous type (64.9%) and 9 cases (9.6%) were meningioma with potential malignancy, ie. hemangloblastic, hemangiopericytic, papillary and anaplastic meningiomas. 3. The common initial clinical features were headache (55.5%), visual disturbance (16.0%) and seizure (14.9%). In radiologic diagnostic tests, there are abnormal findings in over a half on plain skull X-ray and brain CT scan was regarded as a most accurate and safe method. Cerebral angiography provided the informations such as vascularity, venous drainage and relation-ship with sinus of meningioma. 4. Among the 14 cases of basal menlngioma, the surgery could be performed totally in 6 cases and subtotally In 8 and postoperative results were not satisfactory. (3 cases deteriorated and 2 cases dead) 5. In 8 recurrent cases, all the tumors except one case were located at parasagittal area and were 3 hemanglopericytic, 2 hemangioblastic, 2 angiomatous and 1 meningotheliomatous type histologically. 6. The Laser was thought to be very effective surgical tool to remove vascular tumor, such as meningioma, with it's unique properties of non-mechanical bloodless evaporation of tumor and minimizing of brain edema.restrictio

셀 기반 유한차분법을 이용한 시간영역 음향-탄성파 결합 모델링

학위논문(석사) --서울대학교 대학원 :과학교육과(지구과학전공),2009.2.Maste

기공매체에서의 동위원소 이동에 관한 추계학적 모멘트 해석

학위논문(석사) - 한국과학기술원 : 핵공학과, 1989.2, [ v, 34 p. ]The stochastic moments analysis technique is developed to investigate radionuclide migration in geologic porous media from the nuclear waste repository. The mechanisms for radionuclide transport are assumed to be advection in the micropore, radioactive decay of the species, and sorption on the pore wall. Two covariance functions of groundwater velocity, retardation factor, and concentration are derived to incorporate the geologic parameter uncertainty in porous media of small medium dispersivity. The parametric studies show that the correlation length of groundwater velocity has significant influence on the migration behavior of radionuclide. Macrodispersivity is dominantly affected by the fluctuation of groundwater velocity, while the fluctuation of retardation factor has a considerable effect on the retarded stochastic velocity. The upper estimated concentration evaluated from this stochastic moments analysis can be used as a practical conservative value for the performance assessment of a nuclear waste repository.한국과학기술원 : 핵공학과

Elastic Wave Modeling Using the Cell-based Finite Differences in Anisotropic Media

Since seismic anisotropic features are often found in geological structures, we need to describe anisotropic features in seismic modeling and inversion. Although a number of modeling algorithms were developed to address seismic anisotropy, we still need to develop a simple but accurate modeling algorithm to simulate geological-scale models. For such a modeling algorithm for anisotropic media, we extend a time-domain finite-difference method based on the cell-based grid set to anisotropic media. Considering that the cellbasedfinite-difference method only employs displacements and its accuracy is verified for isotropic Lamb&apos;s problem, we can expect that our anisotropic modeling algorithm can also achieve computational efficiency as well as accuracy. Since any interpolations are not needed in our algorithm, we can alsosimulate a model whose material properties abruptly change. In order to reduce artificial reflections originating from the outer boundaries of a model, we slightly modify Higdon&apos;s absorbing boundary conditions. Numerical examples show that our modeling algorithm can properly address anisotropic features. To qualitatively analyze the accuracy of our algorithm, we need to compare numerical solutions with analytic solutions and also apply it to complicated models.1

Reliability of Early Ambulation after Intradural Spine Sur-gery : Risk Factors and a Preventive Method for Cerebro-spinal Fluid Leak Related Complications

Objective : Cerebrospinal fluid leakage related complications (CLC) occasionally occur after intradural spinal surgery. We sought to investigate the effectiveness of early ambulation after intradural spinal surgery and analyze the risk factors for CLC. Methods : For this retrospective cohort study, we enrolled 314 patients who underwent intradural spinal surgery at a single institution. The early group contained 79 patients who started ambulation after 1 day of bedrest without position restrictions, while the late group consisted of 235 patients who started ambulation after at least 3 days of bed rest and were limited to the prone position after surgery. In the early group, Prolene 6-0 was used as the dura suture material, while black silk 5-0 was used as the dura suture material in the late group. Results : The overall incidence rate of CLC was 10.8%. Significant differences between the early and late groups were identified in the rate of CLC (2.5% vs. 13.6%), surgical repair required (1.3% vs. 7.7%), and length of hospital stay (2.99 vs. 9.29 days) (p&lt;0.05). Logistic regression analysis revealed that CLC was associated with practices specific to the late group (p=0.011) and the revision surgery (p=0.022). Conclusion : Using Prolene 6-0 as a dura suture material for intradural spinal surgery resulted in lower CLC rates compared to black silk 5-0 sutures despite a shorter bed rest period. Our findings revealed that suture - needle ratio related to dura defect was the most critical factor for CLC. One-day ambulation after primary dura closure using Prolene 6-0 sutures appears to be a costeffective and safe strategy for intradural spinal surgery

Intraoperative Monitoring for Cauda Equina Tumors: Surgical Outcomes and Neurophysiological Data Accrued Over 10 Years

Objective: Cauda equina tumors affect the peripheral nervous system, and the validities of triggered electromyogram (tEMG) and intraoperative neurophysiologic monitoring (IOM) are unclear. We sought to evaluate the accuracy and relevance of tEMG combined with IOM during cauda equina tumor resection. Methods: Between 2008 and 2018, an experienced surgeon performed cauda equina tumor resections using tEMG at a single institution. A cauda equina tumor was defined as an intradural-extramedullary or intradural-extradural tumor at the level of L2 or lower. The clinical presentation, extent of resection, pathology, recurrence, postoperative neurological outcomes, and intraoperative tEMG mapping and IOM data were retrospectively analyzed. Results: One hundred three patients who underwent intraoperative tEMG were included; 38 underwent only tEMG (tEMG-only group), and 65 underwent a combination of tEMG and multimodal IOM (MIOM group). There were no significant differences between the neurologic outcomes, extents of resection, or recurrence rates of the 2 groups. No significant therapeutic benefit was observed; however, the accuracy of intraoperative predetection improved with the combination of IOM and tEMG (accuracy: tEMG-only group, 86.8%; MIOM group, 92.3%). When the involved rootlet was resected despite the positive tEMG result, motor function worsened in 3 of 8 cases. The sensitivity and specificity of tEMG were 37.5% and 94.7%, respectively. Conclusion: tEMG is an essential adjunctive surgical tool for deciding on and planning for rootlet resection. If the tEMG finding is negative, complete resection, involving the rootlet, may be safe. The accuracy may be further improved by using a combination of tEMG and IOM