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Science of The Total Environment | 2015

Concentrations of phthalate metabolites in breast milk in Korea: Estimating exposure to phthalates and potential risks among breast-fed infants

Sunmi Kim; Jangwoo Lee; Jeongim Park; Hai Joong Kim; Geumjoon Cho; Gun Ha Kim; So Hee Eun; Jeong Jae Lee; Gyuyeon Choi; Eunsook Suh; Sooran Choi; Sungjoo Kim; Young Don Kim; Sung Koo Kim; Su Young Kim; Seunghyo Kim; Soyong Eom; Hyo-Bang Moon; Sungkyoon Kim; Kyungho Choi

Phthalates have been associated with endocrine disruption and developmental effects in many experimental and epidemiological studies. Developing infants are among the most susceptible populations to endocrine disruption. However, limited information is available on phthalate exposure and its associated risks among breast-fed newborn infants. In the present study, breast milk samples were collected from 62 lactating mothers at 1 month post-partum from four cities of Korea in 2012 and were evaluated for six phthalate metabolites (mono-isobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), mono(2-ethyl-hexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and monoethyl phthalate (MEP)). MEP was detected in all breast milk samples, with a median concentration of 0.37 μg/L, and MiBP, MnBP and MEHP were detected in 79-89% of samples, with median concentrations of 1.10, 1.70, and 2.08 μg/L, respectively. However, MEHHP and MEOHP, the oxidized forms of di-ethyl-hexyl phthalate (DEHP), were detected in only one sample. For exposure assessment, the levels of phthalate diesters were estimated based on the parent:metabolite ratios in the breast milk that are reported elsewhere. For risk assessment, the endocrine-related toxicity of the monoester was assumed to be the same as that of its diester form. Median daily intake estimates of phthalates, including both monoester and diester forms, through breast milk consumption ranged between 0.91 and 6.52 μg/kg body weight (bw) for DEHP and between 0.38 and 1.43 μg/kg bw for di-n-butyl phthalate (DnBP). Based on the estimated daily intake, up to 8% of infants exceeded the reference dose of anti-androgenicity (RfD AA) for DEHP, and 6% of infants exceeded the tolerable daily intake (TDI) for DnBP. Breast milk MiBP and MnBP concentrations showed significant positive associations with maternal consumption of whipped cream or purified water. Considering vulnerability of young infants, efforts to mitigate phthalate exposure among lactating women are warranted.


Journal of Epidemiology and Community Health | 2016

Association of diethylhexyl phthalate with obesity-related markers and body mass change from birth to 3 months of age

Jin Hee Kim; Hyunkyung Park; Jangwoo Lee; Geumjoon Cho; Sooran Choi; Gyuyeon Choi; Su Young Kim; So Hee Eun; Eunsook Suh; Sung Koo Kim; Hai Joong Kim; Gun Ha Kim; Jeong Jae Lee; Young Don Kim; Soyong Eom; Seunghyo Kim; Hyo-Bang Moon; Jeongim Park; Kyungho Choi; Sungjoo Kim; Sungkyoon Kim

Background Several studies have suggested potential links of phthalates to obesity in children and adults. Limited evidence, however, has been available for the relations between diethylhexyl phthalate (DEHP) and obesity-related markers or body mass change in early life. Methods 128 healthy pregnant women were recruited and, after delivery, their newborns’ first urine and umbilical cord blood samples were collected. We measured urinary levels of two DEHP metabolites, mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP). We also measured the levels of leptin, total cholesterol and triglyceride (TG) in cord serum, and used them along with weight, length, head circumference and ponderal index (PI, 100u2005g/cm3) at birth, as obesity-related markers, and estimated the relations between DEHP metabolites and obesity-related markers using generalised linear models. For the evaluation of body mass increase by early life DEHP exposure, body mass index (BMI) z-score change during 3u2005months after birth by DEHP metabolites in the first urine samples of the newborns were evaluated using logistic regression. Results DEHP exposure was associated with decrease of PI and increase of TG (PI, β=−0.11, p=0.070 and TG, β=0.14, p=0.027), especially for boys (PI, β=−0.13, p=0.021; and TG, β=0.19, p=0.025). Moreover, DEHP exposure was positively associated with body mass increase during 3u2005months after birth (change of BMI z-scores, OR=4.35, p=0.025). Conclusions Our findings suggest that DEHP exposure may affect body mass change in early life through changes of obesity-related markers.


Science of The Total Environment | 2014

Occurrence and exposure assessment of polychlorinated biphenyls and organochlorine pesticides from homemade baby food in Korea

Yunsun Jeong; Sunggyu Lee; Sunmi Kim; Sung-Deuk Choi; Jeongim Park; Hai Joong Kim; Jeong Jae Lee; Gyuyeon Choi; Sooran Choi; Sungjoo Kim; Su Young Kim; Young Don Kim; Geumjoon Cho; Eunsook Suh; Sung Koo Kim; So Hee Eun; Soyong Eom; Seunghyo Kim; Gun Ha Kim; Kyungho Choi; Sungkyoon Kim; Hyo-Bang Moon

Data on the residue levels of persistent organic pollutants (POPs) in baby food samples are scarce. This is the first study to explore current contamination status and exposure assessment of organochlorines (OCs), including polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), in baby food from Korea. In this study, the concentrations of OCs were determined in homemade baby food samples (n=100) collected from 6-, 9-, 12- and 15-month-old infant groups. The average concentrations of PCBs, dichloro-diphenyl-trichloroethanes (DDTs), hexachlorocyclohexanes (HCHs) and chlordanes (CHLs) in baby food samples were 37.5, 96.6, 26.0, and 13.2 pg/g fresh weight, respectively. The major compounds were CBs 28, 153, 52, and 33 for PCBs and p,p-DDE, p,p-DDT and β-HCH for OCPs. The contribution of DDTs to the total OC concentrations increased from 30% (6-month-old infants) to 67% (15-month-old infants) with increasing infant age, while the concentrations of PCBs, HCHs and CHLs gradually decreased with increasing infant age, suggesting that highest priority for risk reduction of DDTs. The estimated daily intakes (EDIs) of OCs in Korean infants from baby food consumption were lower than the thresholds proposed by the United States Environmental Protection Agency and Health Canada, implying limited potential health risks. However, considering simultaneous exposure from baby food and breast milk consumption, chlordanes and heptachlor epoxide posed potential health risks. Considering the importance of early development and the vulnerability of infants, it is essential to perform systematic monitoring and management programs of OCs in baby food for risk reduction in Korean infants.


Environmental Research | 2016

Occurrence and prenatal exposure to persistent organic pollutants using meconium in Korea: Feasibility of meconium as a non-invasive human matrix.

Yunsun Jeong; Sunggyu Lee; Sunmi Kim; Sung-Deuk Choi; Jeongim Park; Hai Joong Kim; Jeong Jae Lee; Gyuyeon Choi; Sooran Choi; Sungjoo Kim; Su Young Kim; Young Don Kim; Geumjoon Cho; Eunsook Suh; Sung Koo Kim; So Hee Eun; Soyong Eom; Seunghyo Kim; Gun Ha Kim; Sungkyoon Kim; Kyungho Choi; Hyo-Bang Moon

Prenatal exposure to persistent organic pollutants (POPs) is of great concern due to the vulnerability of fetus. Nineteen Polychlorinated biphenyls (PCBs), 18 organochlorine pesticides (OCPs) including DDTs, HCHs, chlordanes, and hexachlorobenzene, and 22 polybrominated diphenyl ethers (PBDEs) were measured in meconium samples from 72 newborn infants using high resolution gas chromatography/mass spectrometry. The median concentrations (on wet weight basis) of PCBs, OCPs, and PBDEs were 26.8pg/g, 66.7pg/g, and 2.32pg/g, respectively. Highly significant correlations were observed among the compounds of PCBs and OCPs, suggesting their similar sources and kinetic behaviors. BDE 47 had significant correlations with PCBs and OCPs, whereas BDE 209 was not correlated with any of the contaminants due to different exposure sources. The concentrations of p,p-DDE, β-HCH, and trans-nonaCHL between paired maternal blood-meconium and cord blood-meconium showed significant correlations, while PCBs and PBDEs were not significantly correlated in the paired samples. Maternal age and gestational age were demographic parameters affecting POP levels in meconium. Multiple regression analysis showed that the levels of several OCPs in cord and maternal serum were contributing factors governing the levels of these contaminants in meconium. Our results indicate that meconium can be utilized as a human matrix for prenatal exposure to several OCPs.


Environmental Research | 2014

Infant exposure to polybrominated diphenyl ethers (PBDEs) via consumption of homemade baby food in Korea.

Yunsun Jeong; Sunggyu Lee; Sunmi Kim; Sung-Deuk Choi; Jeongim Park; Hai Joong Kim; Jeong Jae Lee; Gyuyeon Choi; Sooran Choi; Sungjoo Kim; Su Young Kim; Young Don Kim; Geumjoon Cho; Eunsook Suh; Sung Koo Kim; So Hee Eun; Soyong Eom; Seunghyo Kim; Gun Ha Kim; Won Chan Lee; Kyungho Choi; Sungkyoon Kim; Hyo-Bang Moon

Limited data are available on the residue levels of polybrominated diphenyl ethers (PBDEs) in baby food. In this study, 24 PBDE congeners were determined in 147 homemade baby food samples collected from 97 households for 6-, 9-, 12-, 15-, and from 24 to 27-month-old infant groups during the period of 2012-2013. The concentrations of total PBDEs (ΣPBDE) ranged from 24.5 to 6000 (mean: 263) pg/g fresh weight, higher than those found in commercial formulae from the United States. The predominant congeners were BDEs 209 and 47, accounting for 92% of the ΣPBDE concentrations, reflected by high deca-BDE consumption in Korea. The residue levels and detection rates of BDE 47 in the baby food samples showed a gradual increasing trend with an increase in infant ages, due to changes in the food ingredients from hypoallergenic to greasy. The daily intakes of BDEs 47 and 209 via baby food consumption ranged from 0.04 to 0.58, 0.80 to 20.3, and 1.06 to 22.3 ng/kg body weight/day for 6-, 9-, 12-, 15-, and 24-27-month-old infant groups, respectively; these intakes were lower than the oral reference doses proposed by the US EPA. Together with three exposure sources, baby food, breast milk and dust ingestion for 6-month-old infants, the daily intake of ΣPBDE was 25.5 ng/kg body weight/day, which was similar to the intake via baby food consumption only for over 24-month-old infants in our study. This indicates that baby food is an important exposure pathway of PBDEs for over 24-month-old infants. This is the first study regarding the occurrence and exposure assessment of PBDEs via homemade baby food.


Science of The Total Environment | 2018

Association between maternal exposure to major phthalates, heavy metals, and persistent organic pollutants, and the neurodevelopmental performances of their children at 1 to 2 years of age- CHECK cohort study

Sunmi Kim; Soyong Eom; Hai Joong Kim; Jeong Jae Lee; Gyuyeon Choi; Sooran Choi; Sungjoo Kim; Su Young Kim; Geumjoon Cho; Young Don Kim; Eunsook Suh; Sung Koo Kim; Seunghyo Kim; Gun Ha Kim; Hyo-Bang Moon; Jeongim Park; Sungkyoon Kim; Kyungho Choi; So Hee Eun

Exposure of the developing fetus and infants to toxic substances can cause serious lifelong health consequences. Several chemicals have been associated with adverse neurodevelopmental disorders in the early life stages of humans. However, most epidemiological studies have focused on a limited number of chemicals, and hence may exclude important chemicals from consideration or result in conclusions built on associations by chance. In the present study, we investigated the chemical exposure profile of the women, and associated these with the early neurodevelopmental performance of their offspring at 13-24months of age. The chemicals assessed include four phthalates, bisphenol A, three heavy metals, 19 polychlorinated biphenyls (PCBs), 19 organochlorine pesticides, and 19 polybrominated diphenyl ethers, which were measured from urine, whole blood, serum, and/or breastmilk of the pregnant or lactating women. For neurodevelopmental performance, the Bayley Scales of Infant Development-II (BSID-II), Social Maturity Scale (SMS), and Child Behavior Checklist (CBCL) were measured from a total of 140 toddlers. Among the measured chemicals, monoethyl phthalate (MEP) in maternal urine was significantly associated with early mental, psychomotor, and social development. In addition, breast milk di-ethylhexyl phthalate (DEHP) metabolite and blood lead concentrations were inversely associated with mental and psychomotor development indices, respectively. Maternal blood PCB153, heavy metals, and urinary MEP levels were also higher among the children with behavioral problems, as indicated by the CBCL range. Taken together, maternal exposure to several EDCs such as PCBs and DEHP was associated with adverse neurodevelopmental performances among the children aged 1-2years. Confirmation of these association in larger populations, as well as longer-term consequences of such exposure warrant further investigation.


Obstetrics & gynecology science | 2016

Uterine rupture in pregnancies following myomectomy: A multicenter case series.

Hee-Sun Kim; Soo-young Oh; Suk-Joo Choi; Hyun-Soo Park; Geumjoon Cho; Jin-Hoon Chung; Yong-Soo Seo; Sun-Young Jung; Jung-Eun Kim; Su-Hyun Chae; Han Sung Hwang

Objective The purpose of this case series was to retrospectively examine records of cases with uterine rupture in pregnancies following myomectomy and to describe the clinical features and pregnancy outcomes. Methods This study was conducted as a multicenter case series. The patient databases at 7 tertiary hospitals were queried. Records of patients with a diagnosis of uterine rupture in the pregnancy following myomectomy between January 2012 and December 2014 were retrospectively collected. The uterine rupture cases enrolled in this study were defined as follows: through-and-through uterine rupture or tear of the uterine muscle and serosa, occurrence from 24+0 to 41+6 weeks’ gestation, singleton pregnancy, and previous laparoscopic myomectomy (LSM) or laparotomic myomectomy (LTM) status. Results Fourteen pregnant women experienced uterine rupture during their pregnancy after LSM or LTM. Preterm delivery of less than 34 weeks’ gestation occurred in 5 cases, while intrauterine fetal death occurred in 3, and 3 cases had fetal distress. Of the 14 uterine rupture cases, none occurred during labor. All mothers survived and had no sequelae, unlike the perinatal outcomes, although they were receiving blood transfusion or treatment for uterine artery embolization because of uterine atony or massive hemorrhage. Conclusion In women of childbearing age who are scheduled to undergo LTM or LSM, the potential risk of uterine rupture on subsequent pregnancy should be explained before surgery. Pregnancy in women after myomectomy should be carefully observed, and they should be adequately counseled during this period.


Korean Journal of Obstetrics & Gynecology | 2012

TWO PLACENTAS IN SINGLETON PREGNANCY WITH FUSED UMBILICAL CORD: A CASE REPORT

Nayoon Park; Minji Ryu; Geumjoon Cho; Min-Jeong Oh; Hai-Joong Kim; Tak Kim; Sun Haeng Kim; Soon-Cheol Hong

Two placentas in singleton pregnancy with fused umbilical cord which has its own placental insertion site forming 3-vessel cord at fetal end is an extremely rare case. This present case describes two placentas with fused umbilical cord with an episode of vanishing twin syndrome and there seems to be a strong relationship between these two events. A 37-year-old woman, gravid 0, para 0, visited emergency room with an episode of vaginal bleeding without pelvic cramps at 8 weeks and 5 days of gestation and repeated ultrasonic exams revealed reabsorption of vanishing twin and two separate placentas on anterior and posterior body of uterus. At 40 weeks and 4 days, the patient delivered a viable female infant weighing 3,900 g via Cesarean section and postpartum examination of the placentas and membranes confirmed two placentas with fused umbilical cord. Two placentas were almost equal in size and there were 2 cord insertions, 1 into each placenta. The cord at each of the placental disc had marginal insertion site and main placental disc cord had 2 arteries with one vein (3 vessel-cord) whereas side placental disc cord had one artery with one vein (2 vessel-cord). Several hypothesis for this two placentas with fused umbilical cord in singleton pregnancy, were proposed including placenta abnormalities after in vitro fertilization-embryo transfer procedure, succenturiate lobes and fetus in fetus, however, further evaluation is need.


Ultrasound in Obstetrics & Gynecology | 2010

OP38.10: Abdominal adiposity in the first trimester predicts lipid metabolism in pregnancy

Hyo Jin Yoon; Geumjoon Cho; Hye Won Jeong; B. Koo; Yu Chin Paek; Sunghoi Hong; Min-Jeong Oh; Hyo Soo Kim

pregnancies – birth weight greater than 3800 g. The birth weight or EFBW itself is not a good predictor of the mode of delivery. If we exclude twins more than half of the pregnancies (56%) were terminated by CS. Type 1 diabetes itself is not an indication for CS in our department but other complications linked with diabetic pregnancies lead to CS. Macrosomia is not the most frequent indication for CS. The median birth weight in CS is between 3500–3750 g. On the contrary all pregnancies with a EFBW lower than 2500 g were terminated by CS. Conclusions: The accuracy of ultrasound EFBW in type 1 diabetic pregnant women does not differ from non-diabetic pregnancies. Fetal macrosomy is not the most important factor influencing the number of CS. The management of delivery in type 1 diabetic pregnancies is complex and the decision to terminate the pregnancy by CS is influenced by more factors than EFBW.


Ultrasound in Obstetrics & Gynecology | 2010

OP14.06: Characteristics of the pelvic floor during pregnancy by three‐dimensional ultrasound

Geumjoon Cho; Hye-Ri Hong; B. Koo; Hyo Jin Yoon; A. Kang; Hye Won Jeong; Sunghoi Hong; Min-Jeong Oh; Hyo Soo Kim

Objectives: The limited data regarding best management for patients with vasa previa provides a challenge. The current case review was undertaken to examine the role of serial cervical length evaluation in the surveillance of these patients. Methods: This was a retrospective study of cases of vasa previa diagnosed in our obstetric ultrasound database in the past 3 years. Data regarding diagnosis, antenatal course and obstetric outcomes was collected. Results: 13 cases were reported between 2007 and 2010. Antenatal information was available in 13 patients with outcome data for the 9 patients delivering at our institution. 5/13 (38.5%) were nulliparous. 9/13 (69.2%) cases were singleton gestations and 4/13 (30.8%) multiple pregnancies. None of the patients had a previous history of preterm birth. Median gestational age at diagnosis was 18 weeks (range 12–31 weeks). 7/13 (53.8%) of the patients were diagnosed at the first US examination. Serial monitoring of cervical length was performed in the 9 cases followed at our center at variable intervals. One patient with an initial cervical length > 25 mm subsequently had a short cervix at 20 wks (17 mm). She underwent cerclage placement, then presented in preterm labor and delivered by Cesarean section at 24 weeks. Other patient admitted at 33 weeks for cervical shortening, delivered 2 days later. 3/9 (33.3%) of patients were delivered at 34 wks and 3/9 (33.3%) at 35 wks by elective Cesarean section. Bethametasone for fetal lung maturity was given in 7/9 (77.8%) of the cases. Conclusions: Vasa previa was not always recognized at the time of the first ultrasound, but diagnosis occurred in patients undergoing follow up examinations in 46% of cases. Serial measurements of the cervical length in vasa previa patients may help to identify those at risk of preterm birth that would benefit from inpatient care or earlier delivery. Further studies are needed to assess the optimal role of serial assessment of cervical length in antenatal management.

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Eunsook Suh

Soonchunhyang University

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Gyuyeon Choi

Soonchunhyang University

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Kyungho Choi

Seoul National University

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Su Young Kim

Jeju National University

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Sungkyoon Kim

Seoul National University

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