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Dive into the research topics where Hyun Sun Ko is active.

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Featured researches published by Hyun Sun Ko.


Journal of Psychosomatic Obstetrics & Gynecology | 2012

Sleep disturbances in Korean pregnant and postpartum women

Hyun Sun Ko; Jong-Chul Shin; Moon Young Kim; Yeun Hee Kim; Ji-Hyun Lee; Ki Cheol Kil; Hee Bong Moon; Gui-Se-Ra Lee; Kim Sa-Jin; Byung In Kim

This was a prospective, cohort study in Korean pregnant and postpartum women, to estimate the prevalence and patterns of sleep disturbances. The survey was composed of the following validated sleep questionnaires: the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Women’s Health Initiative Insomnia Rating Scale, Berlin Questionnaire for sleep disordered breathing, the international restless leg syndrome (IRLS) Study Group criteria, and the Johns Hopkins Telephone Diagnostic Interview Form (JHTDIF) for RLS. Statistical analyses were performed using SPSS version 18.0. Six hundred eighty-nine women completed sleep surveys. The overall percentage of women with very poor sleep quality (a PSQI score greater than 10), clinically significant insomnia (a total score of 9 or more), excessive daytime sleepiness (a total ESS score of 10 or more), short sleep duration (less than 7 hours per night) were 80.7%, 50.5%, 34.0% and 29.5%, respectively, and all of three parameters became increased as pregnancy progressed and after delivery ( p = 0.002, 0.001, and 0.001, respectively). The overall positive rates in Berlin and RLS questionnaires were 25.4% and 19.4%. In conclusion, sleep disturbances are prevalent among Korean pregnant and postpartum women, and increase significantly as pregnancy progresses and after delivery.


Lupus | 2015

Hydroxychloroquine and pregnancy on lupus flares in Korean patients with systemic lupus erythematosus

Jung Hee Koh; Hyun Sun Ko; S.-K. Kwok; Ji-Hyeon Ju; S.-H. Park

We investigated the clinical and laboratory characteristics of pregnancies with systemic lupus erythematosus (SLE) and identified lupus flare predictors during pregnancy. Additionally, we examined lupus activity and pregnancy outcomes in SLE patients who continued, discontinued or underwent no hydroxychloroquine (HCQ) treatment during pregnancy. We retrospectively analyzed 179 pregnancies in 128 SLE patients at Seoul St. Mary’s Hospital, Korea, between 1998 and 2012 and then assessed the clinical profiles and maternal and fetal outcomes. Overall, 90.5% of pregnancies resulted in a successful delivery and were divided into two groups: those who experienced lupus flares (80 pregnancies, 44.7%) and those who did not (99 pregnancies, 55.3%). Increased preeclampsia, preterm births, low birth weight, intrauterine growth restriction (IUGR), and low 1-minute Apgar scores occurred in pregnancies with lupus flares compared to pregnancies in quiescent disease. Lupus flares were predicted by HCQ discontinuation, a history of lupus nephritis, high pre-pregnancy serum uric acid and low C4 levels. Our study indicates that achieving pre-pregnancy remission and continuing HCQ treatment during pregnancy are important for preventing lupus flares.


Lupus | 2015

Pregnancy and patients with preexisting lupus nephritis: 15 years of experience at a single center in Korea

Jung Hee Koh; Hyun Sun Ko; J. Lee; Sung-No Jung; S.-K. Kwok; Ji-Hyeon Ju; S.-H. Park

We investigated obstetric outcomes and comorbidities during pregnancy in females with preexisting lupus nephritis (LN) and identified predictors for renal flare. In cases of renal flare during pregnancy, we assessed the long-term post-delivery renal outcome. We performed a retrospective analysis of 183 systemic lupus erythematosus (SLE) pregnancies including blood chemistry, urinalysis, urinary protein, and disease activity recorded at prepregnancy, during pregnancy, and at one month, six months, and one year post-delivery. Pregnancies with preexisting LN had a greater frequency of adverse obstetric outcomes and maternal comorbidity. Renal flares occurred in 50.7% of pregnancies with preexisting LN, 89.2% of which were reactivations. Renal flare among pregnancies with SLE was predicted based on preexisting lupus nephritis (OR 17.73; 95% CI, 5.770–54.484), an active disease prior to pregnancy (OR 2.743; 95% CI, 1.074–7.004), and prepregnancy eGFR < 90 ml/min/1.73 m2 (OR 11.151; 95% CI, 3.292–37.768). Persistent LN one year after delivery was observed in 33.3% of pregnancies. The median follow-up time after delivery was 5.9 (3.1–9.7) years and chronic kidney disease (CKD) occurred in 21.4% of pregnancies with renal flare. In patients with renal flare, failing to achieve a ≥ 50% reduction in urine protein levels within six months, longer total duration of renal flare, and acute kidney injury at renal flare was associated with CKD development. Females with preexisting LN should achieve remission before pregnancy. When patients experience renal flares during pregnancy, it is important to reduce the proteinuria level by >50% within six months and to achieve early remission for excellent long-term renal outcomes.


Reproductive Biology and Endocrinology | 2013

Oncostatin M stimulates cell migration and proliferation by down-regulating E-cadherin in HTR8/SVneo cell line through STAT3 activation

Hyun Sun Ko; Sae Kyung Choi; Hee Kyung Kang; Ho Shik Kim; Ji Hyun Jeon; In Yang Park; Jong Chul Shin

BackgroundDuring 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.MethodsWe 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.ResultsOSM 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.ConclusionsThis 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.


Placenta | 2012

The effects of oncostatin M on trophoblast cells: Influence on matrix metalloproteinases-2 and -9, and invasion activity

Hyun Sun Ko; H.K. Kang; H.S. Kim; Sae Kyung Choi; In-Yang Park; Jong-Chul Shin

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.


Yonsei Medical Journal | 2016

STAT3 and ERK Signaling Pathways Are Implicated in the Invasion Activity by Oncostatin M through Induction of Matrix Metalloproteinases 2 and 9

Hyun Sun Ko; Byung Joon Park; Sae Kyung Choi; Hee Kyung Kang; Ahyoung Kim; Ho Shik Kim; In Yang Park; Jong Chul Shin

Purpose Our previous studies have shown that oncostatin M (OSM) promotes trophoblast invasion activity through increased enzyme activity of matrix metalloproteinase (MMP)-2 and -9. We further investigated OSM-induced intracellular signaling mechanisms associated with these events in the immortalized human trophoblast cell line HTR8/SVneo. Materials and Methods We investigated the effects of OSM on RNA and protein expression of MMP-2 and -9 in the first-trimester extravillous trophoblast cell line (HTR8/SVneo) via Western blot. The selective signal transducer and activator of transcription (STAT)3 inhibitor, stattic, STAT3 siRNA, and extracellular signal-regulated kinase (ERK) siRNA were used to investigate STAT3 and ERK activation by OSM. The effects of STAT3 and ERK inhibitors on OSM-induced enzymatic activities of MMP-2 and -9 and invasion activity were further determined via Western blot and gelatin zymography. Results OSM-induced MMP-2 and -9 protein expression was significantly suppressed by STAT3 inhibition with stattic and STAT3 siRNA silencing, whereas the ERK1/2 inhibitor (U0126) and ERK silencing significantly suppressed OSM-induced MMP-2 protein expression. OSM-induced MMP-2 and MMP-9 enzymatic activities were significantly decreased by stattic pretreatment. The increased invasion activity induced by OSM was significantly suppressed by STAT3 and ERK1/2 inhibition, though to a greater extent by STAT3 inhibition. Conclusion Both STAT3 and ERK signaling pathways are involved in OSM-induced invasion activity of HTR8/SVneo cells. Activation of STAT3 appears to be critical for the OSM-mediated increase in invasiveness of HTR8/SVneo cells.


Journal of Maternal-fetal & Neonatal Medicine | 2016

Sonographic assessment of fetal occiput position during labor for the prediction of labor dystocia and perinatal outcomes.

Sae Kyung Choi; Yong Gyu Park; Da Hye Lee; Hyun Sun Ko; In Yang Park; Jong Chul Shin

Abstract Objectives: To evaluate the effect of the occiput posterior (OP) position on dystocia and perinatal outcomes. Methods: This was a prospective cohort study of 162 primiparous women. We performed intrapartum sonography, and fetal occiput positions were recorded. The relationships between the position of the occiput and the course of labor and perinatal outcomes were investigated. Statistical analysis was performed using SAS 9.2. Results: Fifty-six of 162 fetuses were found to be in the OP position during the first stage of labor. Eight (80.0%) of 10 fetuses in the OP position during the second stage were among the 56 that were in OP position during the first stage. The rate of cesarean sections performed in the OP position group during the first stage was significantly higher than the rate in the non-OP position group (37.5% versus 8.5%, p < 0.0001). The duration of the second stage of labor was longer and neonatal complications occurred more frequently in the OP position group during the second stage than in the non-OP position group (77.9  ±  33.4 min versus 52.2  ± 26.6 min, p = 0.0104; 50.0% versus 17.2%, p = 0.0118). Conclusions: The OP position may be a useful predicator for labor dystocia that can lead to poor neonatal outcomes.


Obstetrics & gynecology science | 2015

Knowledge, attitudes, and acceptability about influenza vaccination in Korean women of childbearing age

Hyun Sun Ko; Yun Seong Jo; Yeun Hee Kim; Yong Gyu Park; Hee Bong Moon; Young Joon Lee; Jong Chul Shin

Objective The aims of the present study were to investigate the womens perspective on influenza infection and vaccination and to evaluate how they influence vaccine acceptability, in Korean women of childbearing age. Methods This was a prospective study by random survey of women of childbearing age (20 to 45 years). They were asked to complete a questionnaire assessing their knowledge, attitudes and acceptability of influenza vaccination before and during pregnancy. This study utilized data from the Korea National Health and Nutrition Examination Survey (KNHANES) between 2008 and 2012, to analyze the recent influenza vaccination trends. Results According to KNHANES (2008-2012), influenza vaccination rates in women of childbearing age have increased up to 26.4%, after 2009. The questionnaire was completed by 308 women. Vaccination rate during pregnancy or planning a pregnancy was 38.6%. The immunization rate increased significantly with the mean number of correct answers (P<0.001). Women who received influenza vaccination were more likely to be previously informed of the recommendations concerning the influenza vaccination before or during pregnancy, received the influenza vaccination in the past, and of the opinion that influenza vaccination is not dangerous during pregnancy, with odds ratios of 14.6 (95% confidence interval [CI], 6.44 to 33.33; P<0.0001), 3.6 (95% CI, 1.84 to 6.97; P=0.0002) and 2.7 (95% CI, 1.34 to 5.47; P=0.0057). Conclusion Influenza vaccination rate in women of childbearing age has increased in this study and national data. More information and recommendation by healthcare workers, especially obstetricians, including safety of vaccination, might be critical for improving vaccination rate in women of childbearing age.


Journal of Obstetrics and Gynaecology Research | 2013

Mesenchymal hamartoma of the chest wall: prenatal sonographic manifestations.

Jeong Ha Wie; Ju Yeon Kim; Ji Young Kwon; Hyun Sun Ko; Jong Chul Shin; In Yang Park

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.


Pregnancy Hypertension: An International Journal of Women's Cardiovascular Health | 2017

The efficacy of peripartum transthoracic echocardiography in women with preeclampsia

Sae Kyung Choi; Jong Chul Shin; Yong Gyu Park; In Yang Park; Ji Young Kwon; Hyun Sun Ko; Yeon Hee Kim

OBJECTIVE To examine the features and efficacy of transthoracic echocardiography (TTE) in preeclampsia. METHODS We retrospectively reviewed the medical records of 145 pregnant women with preeclampsia, who underwent TTE at Seoul St. Marys Hospital between July 2006 and June 2016. We analyzed echocardiographic features in preeclampsia and the relationship between the severity of preeclampsia and TTE findings. Additionally, we examined the predictive echocardiographic factors of persistent hypertension and calculated the adjusted odds ratio (OR) and 95% confidence interval (CI) for multiple regression models by considering systolic and diastolic blood pressure and pre-pregnancy body mass index (BMI). RESULTS Hemodynamic findings assessed by TTE in women with preeclampsia included systolic and diastolic dysfunction, increased left ventricular mass, and enlarged left atrium. Diastolic dysfunction and left ventricular hypertrophy (LVH) were more common in preeclampsia with severe features (39.84% vs. 32.05%, p=0.010, and 21.79% vs. 8.96%, p=0.041, respectively). In the patients with systolic dysfunction, the adjusted OR for persistent hypertension was 17.41 (95% CI=2.83-107.20). The ORs for grade 1 and grade 2 diastolic dysfunction were 12.58 and 32.84, respectively (95% CI, 2.99-52.92 and 3.61-298.58, respectively). When LVH assessed by TTE was considered with diastolic dysfunction, the risk for persistent hypertension increased (OR 19.28; 95% CI-4.36-85.20). CONCLUSION TTE not only can reveal the severity of preeclampsia, but also can be a useful tool for the follow-up of persistent hypertension.

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Jong Chul Shin

Catholic University of Korea

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In Yang Park

Catholic University of Korea

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Sae Kyung Choi

Catholic University of Korea

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Yong Gyu Park

Catholic University of Korea

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Gui-Se-Ra Lee

Catholic University of Korea

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Jeong Ha Wie

Catholic University of Korea

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Sa Jin Kim

Catholic University of Korea

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Jong-Chul Shin

The Catholic University of America

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In-Yang Park

The Catholic University of America

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Yeon Hee Kim

Catholic University of Korea

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