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Dive into the research topics where Ook Hwan Choi is active.

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Featured researches published by Ook Hwan Choi.


Journal of Assisted Reproduction and Genetics | 2001

Clinical Assisted Reproduction: Cumulus Cells Apoptosis as an Indicator to Predict the Quality of Oocytes and the Outcome of IVF–ET

Kyu Sup Lee; Bo Sun Joo; Yong Jin Na; Man Soo Yoon; Ook Hwan Choi; Won Whe Kim

AbstractPurpose: Our purpose was to establish an evaluation system for oocyte quality based on the incidence of cumulus cells apoptosis and to examine the effect of coculture, using autologous cumulus cells, on the outcome of IVF–ET according to proliferative activities of helper cells and the incidence of cumulus cells apoptosis. Methods: Cumulus cell masses were collected from 91 mature oocytes among 330 oocytes retrieved from a total of 34 IVF–ET cycles with tubal infertility and unexplained infertility. The incidence of apoptosis in cumulus cells was assessed by apoptosis detection kit fluorescein. On ovum pick up, 2nd day embryos were cocultured with autologous cumulus cells. Prior to coculture, in vitro proliferative activity of cumulus cells was evaluated. Results: Cumulus cells from patient groups over 40 years old had a significantly increased apoptosis incidence, a lower fertilization rate, and the decreased number of oocytes retrieved compared to the other age groups (P < .05). The incidence of cumulus cells apoptosis was significantly lower when the number of oocytes retrieved was 5 or less (P < .05). Cumulus cells from fertilized oocytes (0.43 ± 0.07%) and those from patients who became pregnant (0.44 ± 0.11%) following IVF–ET showed a significantly lower incidence of apoptosis compared to those of unfertilized oocytes (1.80 ± 0.35%; P < .001) and the nonpregnant group (0.81 ± 0.10%; P < .05). Embryo quality also had a negative correlation with the incidence of cumulus cells apoptosis. Coculture of fertilized oocytes with cumulus cells with high proliferative activity resulted in improved rates of implantation and pregnancy compared to that with poor active cumulus cells. No significant difference was found between the in vitro proliferative activity of cumulus cells and the incidence of cumulus cells apoptosis (P < .063). Conclusions: The age of women might influence the incidence of apoptosis in cumulus cells, and the increased incidence of apoptosis is associated with the number of oocytes retrieved, the fertilization rate, and the pregnancy outcome following IVF–ET. These results suggest that the incidence of cumulus cells apoptosis can be used in predicting oocyte quality, outcome of IVF–ET, and age-related decline in fertility.


Journal of Assisted Reproduction and Genetics | 2000

Relationships Between Concentrations of Tumor Necrosis Factor-α and Nitric Oxide in Follicular Fluid and Oocyte Quality

Kyu Sup Lee; Bo Sun Joo; Yong Jin Na; Man Soo Yoon; Ook Hwan Choi; Won Whe Kim

AbstractPurpose: Our objective was to explain a relationshipbetween concentrations of tumor necrosis factor-α (TNF-α)and nitric oxide (NO) in follicular fluid, oocyte quality, andoutcomes of in vitro fertilization=nembryo transfer (IVF-ET). Methods: The concentrations of TNF-α and NO weremeasured in 115 follicular fluid samples collected from 43patients undergoing IVF-ET program, due to tubalobstruction, some with endometriosis (8 patients) or hydrosalpinx(5 patients). A correlation of these factors concentrationsand the oocyte quality, the oocyte maturity, andinfertility-associated diseases was analyzed. Results: No correlation was found between concentrationsof NO and TNF-α in follicular fluid. NO concentrations infollicular fluids were significantly higher in patients withendometriosis (P < 0.001) or hydrosalpinx (P < 0.01)compared to the patients with just tubal obstruction. FollicularNO concentration differences according to oocyte maturityand oocyte quality were not found. In contrast, TNF-αconcentrations in follicular fluids were significantly higher inpoor quality oocytes (P < 0.05) but were not associatedwith infertility-associated diseases, such as hydrosalphinxor endometriosis, and the oocyte maturity. No significantdifferences in follicular levels of NO and TNF-α as well asIVF-ET parameters of pregnant and nonpregnant groupswere revealed. Conclusions: There is no significant correlation betweenthe concentrations of NO and TNF-α in follicular fluid. NOlevels in follicular fluid are altered in infertility-associateddiseases. However, TNF-α levels but not NO levels influenceoocyte quality. These results suggest that the production ofNO and TNF-α in follicular fluid may be regulated viadifferent pathways and can be tempered withinfertility-associated diseases, thereby influencing oocyte qualitylocally.


Journal of Menopausal Medicine | 2013

A Case of Torsion of a Subserosal Leiomyoma

Hwi Gon Kim; Yong Jung Song; Yong Jin Na; Ook Hwan Choi

Uterine leiomyoma is one of the most common gynecological tumor, whereas acute torsion of the uterine leiomyoma is very rare. We report a case of subserosal leiomyoma that was first detected by ultrasonography, and further confirmed as torsion of subserosal leiomyoma by laparoscopic surgery.


Korean Journal of Obstetrics & Gynecology | 2011

Comparison with human amniotic membrane- and adipose tissue-derived mesenchymal stem cells

In Seob Hwang; Hwi Gon Kim; Deok Hyeon Jo; Dong Hyung Lee; Yun Hee Koo; Yong Jung Song; Yong Jin Na; Ook Hwan Choi

Mesenchymal stem cells (MSC) have been considered as an ideal source of stem cells because of low immunogenicity and availability of autologous cells. Although it has been reported that amniotic membrane contains MSC, the difference between amniotic membrane–derived mesenchymal stem cells (AMSC) and MSC isolated from other tissues is still not clear. This study was designated to compare the characteristics and gene expression profi le of human AMSCs (hAMSC) and adipose tissue-derived mesenchymal stem cells (hADSC).


Journal of Menopausal Medicine | 2014

Sildenafil Inhibits Advanced Glycation End Products-induced sFlt-1 Release Through Upregulation of Heme Oxygenase-1.

Jae Hyeok Jeong; Hwi Gon Kim; Ook Hwan Choi

Objectives We examined the effect of sildenafil citrate on advanced glycation end products (AGEs)-induced soluble fms-like tyrosine kinase 1 (sFlt-1) release in JEG-3 choriocarcinoma cells. Methods Cells were incubated with control bovine serum albumin (BSA) or AGEs-BSA, and expression of sFlt-1 mRNA and protein release was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. AGEs-BSA increased sFlt-1 mRNA expression and protein release in a dose-dependent manner. Results Sildenafil citrate suppressed sFlt-1 mRNA expression and protein release in cells treated with AGEs-BSA in a dose-dependent manner. Likewise, it inhibited the increase of reactive oxygen species (ROS) production and NF-κB activity in these cells. Cobalt protoporphyrin (CoPP) and bilirubin also inhibited sFlt-1 release and ROS production in cells treated with AGEs-BSA, whereas zinc protoporphyrin IX (ZnPP IX) antagonized the effect of sildenafil citrate. In cells transfected with the heme oxygenase-1 (HO-1) siRNA, sildenafil citrate failed to inhibit the sFlt-1 release and ROS production. Conclusion These results strongly suggest that sildenafil citrate inhibits sFlt-1 release and ROS production in cells treated with AGEs-BSA through upregulation of the HO-1 expression in JEG-3 cells.


Obstetrics & gynecology science | 2017

Lymphoepithelioma-like carcinoma of the uterine cervix

Hyun Sil Yun; Sun Kyung Lee; Gun Yoon; Hwi Gon Kim; Dong Hyung Lee; Yong Jin Na; Ook Hwan Choi; Dong Hoon Shin; Yong Jung Song

Lymphoepithelioma-like carcinoma (LELC) of the uterine cervix is exceedingly uncommon. We herein report a rare case of cervical LELC. A 45-year-old woman was admitted to gynecology department with vaginal bleeding for one month. Liquid-based cytology revealed atypical endometrial cells, not otherwise specified on her cervix. On a hysteroscopy, an endocervical mass was identified and the pathologic result was consistent with poorly differentiated squamous cell carcinoma. Magnetic resonance imaging and positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-D-glucose integrated with computed tomography revealed a 3.1-cm endocervical mass without distant metastasis or enlarged lymph nodes. The International Federation of Gynecology and Obstetrics stage was IB1. A radical hysterectomy and bilateral pelvic lymph node dissection were performed. The pathologic diagnosis was a poorly differentiated carcinoma, showing features of LELC. She has been followed for 8 months without adjuvant treatment since the surgery, during which time there has been no evidence of tumor recurrence or metastasis.


Taiwanese Journal of Obstetrics & Gynecology | 2016

The effectiveness of laparoendoscopic single-site surgery (LESS) compared with conventional laparoscopic surgery for ectopic pregnancy with hemoperitoneum

Juseok Yang; Yong Jin Na; Yong Jung Song; Ook Hwan Choi; Sun Kyung Lee; Hwi Gon Kim

OBJECTIVE The purpose of this study was to compare clinical outcomes of conventional laparoscopic surgery and laparoendoscopic single-site surgery (LESS) in the surgical treatment of tubal ectopic pregnancy. MATERIAL AND METHODS A total of 156 patients were diagnosed with ectopic pregnancies by ultrasonography and serum β-human chorionic gonadotrophin (β-hCG) levels at Pusan National University Yangsan Hospital from January 2009 through December 2013. We excluded 28 patients who only received medical treatment, 15 patients who underwent surgery by laparotomy for severe hypovolemic shock, and 30 patients who presented with less than 1 L of hemoperitoneum. Of the 83 patients with massive hemoperitoneum, 38 patients had LESS performed while the remaining 45 patients underwent conventional laparoscopic surgery. RESULTS In this study, there were no statistically significant differences in clinical outcomes in either surgical method except for operative time. Operative time of LESS was significantly shorter than conventional surgery for patients with more than 500 mL of hemoperitoneum. CONCLUSION LESS is a safe and feasible surgical approach in the treatment of tubal ectopic pregnancy. At the same time, LESS has been shown to be more effective than conventional laparoscopic surgery in handling massive hemoperitoneum of more than 1 L, which is a common complication of ectopic pregnancy.


Journal of Menopausal Medicine | 2014

Mitochondrial Channel Opener Diazoxide Attenuates Hypoxia-Induced sFlt-1 Release in Human Choriocarcinoma Cells

Byeong Seop Shin; Hwi Gon Kim; Ook Hwan Choi

Objectives To examine the effect of diazoxide on hypoxia-induced soluble fms-like tyrosin kinase-1 (sFlt-1) release in JEG-3 choriocarcinoma cells. Methods Cells were cultured under normoxia (20% O2) or hypoxia (1% O2), and expression of sFlt-1 mRNA and protein release was determined by quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) assays and enzyme-linked immunosorbent assay (ELISA). Results Tumor necrosis factor-alpha (TNF-α) as well as hypoxia stimulated sFlt-1 release and diazoxide inhibited both of them. The selective inhibitor of mitochondrial adenosine triphosphat (ATP)-sensitive K+ channel opener (KATP) 5-hydroxydecanoate (5-HD) completely reversed the diazoxide-induced inhibition of hypoxia-stimulated sFlt-1 release. qRT-PCR and Western blot analyses showed that diazoxide up-regulated the heme oxygenase-1 (HO-1) expression. In addition, the HO-1 inducer cobalt protoporphyrin (CoPP) and the metabolic product of HO-1 bilirubin mimicked diazoxide to inhibit sFlt-1 release and reactive oxygen species (ROS) production under hypoxia, whereas the HO-1 inhibitor zinc protoporphyrin IX (ZnPP IX) antagonized the effect of diazoxide. In cells transfected with the HO-1 siRNA, diazoxide did not exert any effect on sFlt-1 release and ROS production under hypoxia. Conclusion These results, taken together, strongly suggest that up-regulation of the HO-1 expression is the crucial mechanism responsible for the diazoxide-induced inhibition of the sFlt-1 release and ROS production under hypoxia.


Journal of Menopausal Medicine | 2017

The Relationship between Renal Function and Bone Marrow Density in Healthy Korean Women

Byung Kyu Park; Ka Yeong Yun; Seung Chul Kim; Jong Kil Joo; Kyu Sup Lee; Ook Hwan Choi

Objectives The relationship between renal function and bone mineral density (BMD) is controversial. We evaluated the relationship between markers of renal function and BMD in healthy Korean women. Methods A total of 1,093 women who visited the health promotion center at Pusan National University hospital were included in the cross-sectional study. We divided the study population into two groups by BMD: osteopenia-osteoporosis and normal in the lumbar and femur regions, respectively. We compared the relationship between renal function and BMD using a logistic regression model and used SAS 9.3 (SAS Institute, Inc., Cary, NC, USA) for all statistical analysis. Results Blood urea nitrogen (BUN), creatinine, and cystatin C (Cys-C) were correlated with BMD in both the normal and osteopenia-osteoporosis groups, and in logistic regression analysis, BUN and Cys-C were correlated with lumbar and femur BMD. However, after we adjusted for age, menopause, and body mass index, only creatinine showed a negative correlation with lumbar BMD, and estimated glomerular filtration rate (eGFR) was related positively with femur BMD. Conclusions Serum creatinine could be a marker for lumbar BMD and eGFR for femur BMD in Korean women without overt nephropathy.


Journal of Menopausal Medicine | 2017

A Rare Case of an Autoamputated Ovary with Mature Cystic Teratoma

Hwi Gon Kim; Yong Jung Song; Yong Jin Na; Juseok Yang; Ook Hwan Choi

Autoamputated ovary with mature cystic teratoma (MCT) is a rarely reported gynecologic entity with an unknown prevalence. A 34-year-old woman referred to our clinic for presumed left ovarian tumor. Pelvic examination, ultrasonography and computed tomography scan revealed a 5-cm, cystic ovarian mass with calcification and fat component, and tumor markers were as follows, cancer antigen (CA) 125; 10.4 U/mL, CA19-9; 2 U/mL. Laparoscopy was performed. The mass was identified in the left adnexal region without any ligamentous or direct connection with the pelvic organs. The right ovary was normal. However, the left ovary and the tube could not be identified in its proper anatomical location. The mass was successfully removed with sharp and blunt dissection. A review of histopathologic study revealed a MCT. The patient became pregnant within seven months and gave birth to a healthy baby by cesarean section. We present a rare case of an autoamputated ovary with MCT.

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Yong Jin Na

Pusan National University

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Hwi Gon Kim

Pusan National University

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Yong Jung Song

Pusan National University

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Dong Hyung Lee

Pusan National University

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Hyun Sil Yun

Pusan National University

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Juseok Yang

Pusan National University

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Kyu Sup Lee

Pusan National University

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Sun Kyung Lee

Pusan National University

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Yun Hee Koo

Pusan National University

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Bo Sun Joo

Pusan National University

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