Hyun Sun Ko

Catholic University of Korea, Seoul, Seoul, South Korea

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Publications (29)78.33 Total impact

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    Ultrasound in Obstetrics and Gynecology 10/2013; 42(s1). · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 10/2013; 42(s1). · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 10/2013; 42(s1). · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 10/2013; 42(s1). · 3.56 Impact Factor
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    ABSTRACT: During the first trimester of pregnancy, trophoblastic E-cadherin expression is down-regulated, thereby allowing extravillous trophoblasts (EVTs) to acquire the potential for migration and invasiveness. The aim of the present study was to investigate the role of OSM on the migration and proliferation of EVT cell line HTR8/SVneo with regard to its effects on the expression of E-cadherin and STAT3 activation. We investigated the effects of OSM on RNA and protein expression of E-cadherin by real time RT-PCR analyses, western blotting, and indirect immunofluorescence staining in HTR8/SVneo cells, as well as the effects on cell migration and proliferation. The selective signal transducer and activator of transcription (STAT)3 inhibitor, stattic, and STAT3 siRNA were used to investigate STAT3 activation by OSM. OSM significantly reduced RNA and protein expression of E-cadherin. Indirect immunofluorescence staining of HTR8/SVneo cells also revealed the down-regulation of E-cadherin, compared with the controls. OSM-stimulated cell migration was attenuated by anti-gp130 antibodies. OSM-induced STAT3 phosphorylation, and the down-regulation of E-cadherin by OSM treatment was restored by stattic and STAT3 siRNA. In addition, OSM-stimulated migration and proliferation were significantly suppressed by STAT3 inhibition. This study suggests that OSM stimulates the migration and proliferation of EVTs during the first trimester of pregnancy through the down-regulation of E-cadherin. In addition, this study suggests that the effects of OSM on migration and proliferation are related to STAT3 activation, which is important in trophoblast invasiveness.
    Reproductive Biology and Endocrinology 09/2013; 11(1):93. · 2.14 Impact Factor
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    ABSTRACT: Mesenchymal hamartoma of the chest wall is a rare, benign lesion that arises from one or more ribs, almost exclusively found in infants. Some cases that developed in the fetal period have been reported, but accurate diagnosis was usually possible only after birth, except in a few cases in which fetal magnetic resonance imaging or computed tomography were performed. We present a case of a congenital mesenchymal hamartoma of the chest wall. Although the diagnosis was not confirmed until birth, the prenatal sonographic examination showed strongly suggestive findings. We review the published reports on this condition, and suggest the prenatal sonographic features. Prenatal sonography is valuable in the differential diagnosis of chest mass.
    Journal of Obstetrics and Gynaecology Research 05/2013; · 0.84 Impact Factor
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    ABSTRACT: Objectives The purpose of this study was to evaluate normal nasolabial dimensions using the images of facial profiles in normal Korean fetuses. Methods We conducted a cross-sectional study of 355 normal fetuses at 14 to 39 weeks' gestation. After the exclusion of inadequate images and inadequate numbers of fetuses at 14 to 19 and 37 to 39 weeks' gestation, the sonographic facial profiles from 222 fetuses at 20 to 37 weeks' gestation were evaluated. Five parameters, nose length, nose protrusion, pronasal-subnasal distance, distance between the upper philtrum and mouth, and distance between the tip of the nose and mouth, were measured and are presented according to gestational age. Data were analyzed by intraclass correlation coefficients and regression analysis. Results There were significant linear correlations between gestational age and nose length (R = 0.390; P < .001), pronasal-subnasal distance (R = 0.415; P < .001), and distance between the upper philtrum and mouth (R = 0.315; P < .001). There were significant quadratic relationships between gestational age and nose protrusion (R(2) = 0.213; P < .001) and distance between the tip of the nose and mouth (R(2) = 0.173; P < .001). Conclusions We provide preliminary normative nasolabial dimensions of facial profiles at 20 to 37 weeks' gestation in normal Korean fetuses. These data may be of help not only in the understanding of normal nasolabial growth in utero but also in the diagnosis of abnormal facial dimensions.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 04/2013; 32(4):617-24. · 1.40 Impact Factor
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    ABSTRACT: PURPOSE: This study was intended to evaluate the attributable risk of obstructive sleep apnea (OSA) by a sleep questionnaire to adverse pregnancy outcomes. METHODS: This was a prospective, cohort study in Korean pregnant women. Berlin questionnaire was employed for symptom-based OSA screening during the third trimester and obstetric outcome data were obtained in 276 deliveries. The relationship between symptom-based OSA and outcomes were explored using SPSS version 18.0 and stratified by obesity (BMI strata <30 and ≥30). Our primary outcome was the compound occurrence of SGA (fetal) or preeclampsia (maternal). Multivariate models were applied in controlling for potential confounders. RESULTS: The overall prevalence of OSA was 32.2 % and it was significantly related with the higher maternal BMI, more body weight at delivery, and weight gain during pregnancy (p = 0.007, p = 0.003, p = 0.005, respectively). There were no significant differences in the primary outcomes according to the positivity of OSA by screening, regardless of the stratification by obesity. The cesarean delivery rate was significantly higher in the OSA positive group (36.0 vs 22.5 %, p = 0.018), but it was not significant in the each strata of obesity. In multivariate analysis, the outcomes of birth weight, preeclampsia, cesarean delivery, and small for gestational age were also not different according to the positivity of OSA. CONCLUSIONS: It seems that the prevalence of OSA by a sleep questionnaire is overestimating OSA in Korean pregnant women. Polysomnography might be needed to diagnose OSA and to evaluate the relationship between OSA and the occurrence of SGA or preeclampsia.
    Archives of Gynecology 10/2012; · 0.91 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 09/2012; 40(S1). · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 09/2012; 40(S1). · 3.56 Impact Factor
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    ABSTRACT: Oncostatin M (OSM), a cytokine of the interleukin-6 (IL-6) family, can either promote or inhibit cell growth in various normal and tumor cells and is expressed in rheumatoid arthritis, multiple sclerosis, multiple myeloma, and other inflammatory conditions. We investigated one of the possible mechanisms involved in trophoblast invasion using the human placental cell line derived from first trimester extravillous trophoblasts (HTR8SVneo): modulation of matrix metalloproteinase (MMP)-2 and -9 expression and enzymatic activity. And we addressed also the effects of exogenous OSM on the in vitro invasion activity of HTR8SVneo cells. We found that OSM enhanced the constitutive RNA and protein expressions of MMP-2 and MMP-9 in HTR8SVneo cell lines. Also, OSM treatment increased significantly the enzymatic activity of MMP-2 on gelatin zymography. The effects OSM on enzymatic activity of MMP-9 was not significant. We found that OSM increased invasion activities of HTR8SVneo cells in time-dependent and dose-dependent manners. This study suggests that OSM enhances invasion activities of extravillous trophoblasts during the first trimester through the increased enzyme activity of gelatinases, especially MMP-2.
    Placenta 08/2012; 33(11):908-13. · 3.12 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate a normal range for prenatal craniofacial inclination using images of fetal profiles at 14 to 39 weeks' gestation in normal Korean fetuses. We conducted a cross-sectional study of 308 normal fetuses at 14 to 39 weeks' gestation. After the exclusion of images with inadequate quality, the sagittal plane of the sonographic fetal facial profile from 250 normal fetuses was evaluated. The frontomaxillary facial, frontonasal, maxilla-nasion-mandibular, and mandibulomaxillary facial angles were measured and are presented according to gestational age. The overall mean frontomaxillary facial angle ± SD was 86.0° ± 7.6° between 14 weeks 6 days' and 39 weeks 2 days' gestation without a significant association between the frontomaxillary facial angle and gestational week. The overall mean frontonasal, maxilla-nasion-mandibular, and mandibulomaxillary facial angles were 125.8° ± 7.2°, 4.7° ± 3.3°, and 83.2° ± 8.5° between 14 weeks and 39 weeks 6 days. There was a significant linear correlation between gestational age and the frontonasal angle (r = -0.1534; P = .0187; y = -0.188 × gestational age + 130.7), maxilla-nasion-mandibular angle (r = -0.2773; P < .0001; y = -0.160 × gestational age + 9.0), and mandibulomaxillary facial angle (r = -0.2861; P < .0001; y = -0.432 × gestational age + 94.6). We provide preliminary normative data for fetal facial angles related to craniofacial inclination across gestational ages in normal Korean fetuses. These data may be of help not only for the understanding of normal facial growth in utero but also for diagnosis of abnormal fetal facial dimensions.
    Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 04/2012; 31(4):569-76. · 1.40 Impact Factor
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    ABSTRACT: p38 Mitogen-activated protein kinase (MAPK) has been considered to be a promising target for the development of therapeutics for various immunologic diseases. Herein we report an example for a successful application of the virtual screening with protein-ligand docking to identify the novel inhibitors of p38α MAPK. These inhibitors were screened for having desirable physicochemical properties as a drug candidate and compound 1-3 revealed a moderate inhibitory activity with IC(50) values ranging from 0.7 to 20 μM. Therefore, they deserve a consideration for further development by structure-activity relationship (SAR) studies to optimize the inhibitory activities. Structural features relevant to the stabilization of the newly identified inhibitors in the ATP-binding site of p38 MAPK are addressed in detail.
    Bioorganic & medicinal chemistry letters 03/2012; 22(6):2195-9. · 2.65 Impact Factor
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    ABSTRACT: The identification of antenatal depression is critical but poorly conducted. The aim of this study was to construct a simplified depression survey scale and to verify its efficacy as a pre-screening for antenatal depression. A total of 494 pregnant women in the third trimester of gestation who had received antenatal care at Seoul St. Mary's Hospital from July 2009 to June 2010 were included. The Edinburgh Postnatal Depression Scale (EPDS) questionnaire was completed by them. The subjects were randomly divided into two groups: 250 of training set and 244 of validation set. We designed a simplified questionnaire comprising two items of EPDS using the training set. We then validated its efficacy with the training set and reaffirmed the results with the validation set. The sum of item 5 (scare or panic) and item 8 (sadness or misery) explained 75.5% of the total score of the EPDS (AUC = 0.947). Using a score of 3 as a cut-off value of the simplified scale, sensitivity was 92.4% and specificity was 86.3%. The positive and negative predictive values were 56.2% and 98.4%, retrospectively. This study suggests that the simplified EPDS can be an efficient instrument to rule out depression during pregnancy.
    International journal of medical sciences 01/2012; 9(1):40-6. · 2.07 Impact Factor
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    ABSTRACT: Congenital lipoid adrenal hyperplasia (CLAH) is caused by mutations to the steroidogenic acute regulatory protein (StAR) gene associated with the inability to synthesize all adrenal and gonadal steroids. Inadequate treatment in an infant with this condition may result in sudden death from an adrenal crisis. We report a case in which CLAH developed in Korean siblings; the second child was prenatally diagnosed because the first child was affected and low maternal serum estriol was detected in a prenatal screening test. To our knowledge, this is the first prenatal diagnosis of the Q258X StAR mutation, which is the only consistent genetic cluster identified to date in Japanese and Korean populations.
    Yonsei medical journal 11/2011; 52(6):1035-8. · 0.77 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 10/2011; 38(S1). · 3.56 Impact Factor
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    Ultrasound in Obstetrics and Gynecology 10/2011; 38(S1). · 3.56 Impact Factor
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    ABSTRACT: This study was undertaken to investigate the pregnancy outcomes in patients with systemic lupus erythematosus (SLE) and the appropriate timing of pregnancy. We performed a retrospective evaluation of 183 pregnancies with SLE at Catholic University Medical Center during the 13-year period from 1998 to 2010. Pregnancy outcomes were compared according to SLE characteristics. The predictive value of the different cut-off points of the stable period before conception on adverse pregnancy outcomes was calculated by ROC (Receiver operating characteristics) curve analysis. In multivariate analysis, the presence of antiphospholipid antibodies (aPLs) increased the risk of pregnancy loss (p<0.0001) and premature birth (p=0.0040). Active disease at conception increased the risk of premature birth (p< 0.0001) and complications (IUGR, PIH, or both) (p= 0.0078). The other predictor of complications was found to be lupus flare (p=0.0252). At a cut-off level of stable period of 4 months before conception, sensitivity and specificity were 70.8% and 53.2%, 71.4% and 61.5%, and 63.6 % and 59.8 %, respectively on reducing pregnancy loss, premature birth, and complications. Pregnancies with aPLs, active disease at conception and SLE flares are at a higher risk of adverse outcomes. It is essential that disease activity remains stable at least 4 months before conception, for favorable pregnancy outcomes.
    International journal of medical sciences 01/2011; 8(7):577-83. · 2.07 Impact Factor
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    ABSTRACT: The purpose of this retrospective cohort study was to elucidate whether the location of placenta below uterine incision in cesarean section is important in the development of maternal complications in placenta previa patients. The study was conducted on 409 patients 414 parturition at 3 hospitals in affiliation with the Catholic Medical Center, Seoul, Korea from May 1999 to December 2009. The subjects were divided to two groups: the group whose placenta was located in the anterior portion of the uterus (anterior group) and the group whose placenta was located in the posterior portion of the uterus (posterior group). And then they are compared to each other. Logistic regression was used to control for confounding factors. In the anterior group, regardless of confounding factors, the incidence of excessive blood loss (OR 2.97; 95% CI: 1.64-5.37), massive transfusion (OR 3.31; 95% CI: 1.33-8.26), placental accreta (OR 2.60, 95% CI: 1.40-4.83), and hysterectomy (OR 3.47, 95% CI: 1.39-8.68) was higher. Sonographic determination of the placental position where its location beneath the uterine incision is very important to predict maternal outcomes in placenta previa patients, and such cases, close attention should be paid for massive hemorrhage.
    International journal of medical sciences 01/2011; 8(5):439-44. · 2.07 Impact Factor
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    ABSTRACT: This study was to compare pregnancy outcomes between cerclage and expectant management in wemen with a dilated cervix. Retrospective multicenter cohort study. Five hospitals of Catholic University Medical Center Network in Korea. A total of 173 women between 14 0/7 and 29 6/7 weeks' gestation with cervical dilation of 1 cm or greater by digital examination. Pregnancy outcomes were compared according to cerclage or expectant management, with the use of propensity-score matching. Primary outcome was time from presentation until delivery (weeks). Secondary outcomes were gestational age at delivery, neonatal survival, morbidity, preterm birth, and so on. Of 173 women, 116 received a cerclage (cerclage group), and 57 were managed expectantly without cerclage (expectant group). Cervical dilation at presentation, and the use of amniocentesis performed to exclude subclinical chorioamnionitis differed between two groups. In the overall matched cohort, there was significant difference in the time from presentation until delivery (cerclage vs. expectant group, 10.6±6.2 vs. 2.9±3.2 weeks, p <0.0001). While there was no significant difference in the neonatal survival between two groups, there were lower neonatal morbidity as well as higher pregnancy maintenance rate at 28, 32, 34 and 37 weeks' gestation in the cerclage group, compared with the expectant group. This study suggests that digital examination-indicated cerclage appears to prolong gestation and decrease neonatal morbidity, compared with expectant management in women with cervical dilation between 14 0/7 and 29 6/7 weeks.
    International journal of medical sciences 01/2011; 8(7):529-36. · 2.07 Impact Factor