• Biomolecules & Therapeutics
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• v.20 no.3
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• pp.280-285
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• 2012

The developing embryo naturally experiences relatively low oxygen conditions in vivo. Under in vitro hypoxia, mouse embryonic stem cells (mESCs) lose their self-renewal activity and display an early differentiated morphology mediated by the hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). Previously, we demonstrated that histone deacetylase (HDAC) is activated by hypoxia and increases the protein stability and transcriptional activity of HIF-$1{\alpha}$ in many human cancer cells. Furthermore HDAC1 and 3 mediate the differentiation of mECSs and hematopoietic stem cells. However, the role of HDACs and their inhibitors in hypoxia-induced early differentiation of mESCs remains largely unknown. Here, we examined the effects of several histone deacetylase inhibitors (HDACIs) on the self-renewal properties of mESCs under hypoxia. Inhibition of HDAC under hypoxia effectively decreased the HIF-$1{\alpha}$ protein levels and substantially improved the expression of the LIF-specific receptor (LIFR) and phosphorylated-STAT3 in mESCs. In particular, valproic acid (VPA), a pan HDACI, showed dramatic changes in HIF-$1{\alpha}$ protein levels and LIFR protein expression levels compared to other HDACIs, including sodium butyrate (SB), trichostatin A (TSA), and apicidin (AP). Importantly, our RT-PCR data and alkaline phosphatase assays indicate that VPA helps to maintain the self-renewal activity of mESCs under hypoxia. Taken together, these results suggest that VPA may block the early differentiation of mESCs under hypoxia via the destabilization of HIF-$1{\alpha}$.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.3
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• pp.221-226
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• 2020

Objective: We attempted to identify the optimal cutoff numbers of mature oocytes that would produce at least one or multiple top-quality (grade A) day-3 embryos in normal responders undergoing stimulated in vitro fertilization (IVF) cycles. Methods: We selected 210 fresh IVF cycles performed in 170 infertile women at a single center from January 2014 to November 2019. Four to 14 (total) oocytes were obtained in all cycles after conventional ovarian stimulation. A receiver operating characteristic curve analysis was performed to find the moderate and extreme cutoff numbers of mature oocytes that would produce ≥ 1, ≥ 2, ≥ 3, ≥ 4, and ≥ 5 top-quality embryos. Results: The cutoff number of mature oocytes was significantly correlated with the number of top-quality embryos (r = 0.467, p= 0.000). The moderate cutoff number of mature oocytes was ≥ 3, ≥ 5, ≥ 5, ≥ 6, and ≥ 6 for obtaining ≥ 1, ≥ 2, ≥ 3, ≥ 4, and ≥ 5 top-quality embryos, respectively. The extreme cutoff number of mature oocytes was ≥ 9, ≥ 9, ≥ 10, ≥ 10, and ≥ 11 for obtaining ≥ 1, ≥ 2, ≥ 3, ≥ 4, and ≥ 5 top-quality embryos, respectively. Conclusion: We present the optimal cutoff numbers of mature oocytes that would yield ≥ 1, ≥ 2, ≥ 3, ≥ 4, and ≥ 5 top-quality embryos with 95% specificity. Our findings could help infertility clinicians to set target mature oocyte numbers in women undergoing stimulated IVF cycles.

• Journal of Life Science
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• v.14 no.1
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• pp.26-31
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• 2004

Redox factor-1 (Ref-1), known as a redox regulator, controls the DNA binding of AP-1 and is activated in HT29 colon cancer cells by hypoxia in vitro. REF-1 also increases tile DNA binding affinity of Hypoxia-inducible Factor-lalpha$ (HIF-lalpha$), HIF-like Factor (HLF) and early growth response-1 (Egr-1) which induce expression of the genes involved in angiogenesis, so that we speculate that REF-1 may play a role in hypoxia-induced angiogenesis. In this research we tried to detect novel proteins interacting with REF-1 using Yeast two-hybrid system using full-length REF-1 cDNA as bait. As result of such screening we detected 3 positive clones. DNA sequencing and GeneBank search revealed that one of the clones contained the same sequences as M.musculus cDNA for tioredoxin.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.2
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• pp.119-125
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• 2016

Objective: The aim of this study was to report a case series of in vitro matured (IVM) oocyte freezing in gynecologic cancer patients undergoing radical surgery under time constraints as an option for fertility preservation (FP). Methods: Case series report. University-based in vitro fertilization center. Six gynecologic cancer patients who were scheduled to undergo radical surgery the next day were referred for FP. The patients had endometrial (n=2), ovarian (n=3), and double primary endometrial and ovarian (n=1) cancer. Ex vivo retrieval of immature oocytes from macroscopically normal ovarian tissue was followed by mature oocyte freezing after IVM or embryo freezing with intracytoplasmic sperm injection. Results: A total of 53 oocytes were retrieved from five patients, with a mean of 10.6 oocytes per patient. After IVM, a total of 36 mature oocytes were obtained, demonstrating a 67.9% maturation rate. With regard to the ovarian cancer patients, seven IVM oocytes were frozen from patient 3, who had stage IC cancer, whereas one IVM oocyte was frozen from patient 4, who had stage IV cancer despite being of a similar age. With regard to the endometrial cancer patients, 15 IVM oocytes from patient 1 were frozen. Five embryos were frozen after the fertilization of IVM oocytes from patient 6. Conclusion: Immature oocytes can be successfully retrieved ex vivo from macroscopically normal ovarian tissue before radical surgery. IVM oocyte freezing provides a possible FP option in patients with advanced-stage endometrial or ovarian cancer without the risk of cancer cell spillage or time delays.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.3
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• pp.157-163
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• 2016

Objective: The decision to use in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or split insemination (IVF-ICSI) in the first cycle is based on the number of motile sperm. Hence, total fertilization failure (TFF) often occurs during IVF cycles, despite normozoospermia. To investigate whether the cumulative motile swim-up spermatozoa percentage at 22 hours post-insemination (MSPPI) is an indicator for ICSI, we analyzed TFF, fertilization, blastocyst development, chemical pregnancy, clinical pregnancy, and live birth rates. Methods: This prospective study was performed using data obtained from 260 IVF cycles. At 22 hours after insemination, the remaining swim-up spermatozoa were observed and divided into six groups according to MSPPI (<10%, 10% to <30%, 30% to <50%, 50% to <70%, 70% to <90%, and 90% to 100%). Results: Regardless of the ejaculated motile sperm concentration ($0.6-280{\times}10^6/mL$ motile spermatozoa), the incidence of TFF significantly increased when MSPPI was <10%, and the fertilization rate significantly decreased when MSPPI was <30%. We found that cumulative MSPPI correlated with the cumulative fertilization rate (Spearman correlation, 0.508, p<0.001). Regarding embryo development, we observed no significant differences in the rates of blastocyst development, chemical pregnancy, clinical pregnancy, or live birth among all groups. Conclusion: Our findings suggest that MSPPI is a viable indicator for split IVF-ICSI and ICSI. Taken together, by employing the MSPPI test in advance before IVF, ICSI, or split IVF-ICSI cycles, unnecessary split IVF-ICSI and ICSI may be avoided.

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.73-78
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• 2000

Embryonic stem (ES) cells are pluripotent cell lines, which derived from preimplantation embryo. These cells have been used as a vehicle of foreign DNA for production of transgenic mammals. this experiment was performed to examined the possible use of blastodermal cells derived from hen's egg for germline manipulation. Stage X blsdtodermal cells isolated from fertilized eggs were cultured in DMEM containing 15% fetal calf serum. Blastodermal cells wre co-cultured on the chicken embryonic fibroblast (CEF) or mouse embryonic fibroblast(MEF) cells. to examine the effects of growth factors on stem cell growth, bFGF and LIF were added. There was no significant difference in colony formation of putative ES cells between CEF and MEF as a feederlayer, but the addition of growth factors enhanced the proliferation and inhibited differentiation of blastodermal cells. To characterize the cell colonies as a putative ES cells, putative embryonic cell colonies were stained by periodic acid Schiffs (PAS) reagent. The putative ES cell colonies showed intensive positive reaction similar to the property of undifferentiated PGC upto 20days in vitro, but not in other cell types. this result demonstrates that PAS-positive cell colonies may be used for the study of establishment of chicken ES cell lines for the production of transgenic chicken.

• Molecules and Cells
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• v.19 no.1
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• pp.46-53
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• 2005

Human embryonic stem (hES) cells, unlike most cells derived from adult or fetal human tissues, represent a potentially unlimited source of various cell types for basic clinical research. To meet the increased demand for characterized hES cell lines, we established and characterized nine new lines obtained from frozen-thawed pronucleus-stage embryos. In addition, we improved the derivation efficiency from inner cell masses (to 47.4%) and optimized culture conditions for undifferentiated hES cells. After these cell lines had been maintained for over a year in vitro, they were characterized comprehensively for expression of markers of undifferentiated hES cells, karyotype, and in vitro/in vivo differentiation capacity. All of the cell lines were pluripotent, and one cell line was trisomic for chromosome 3. Improved culture techniques for hES cells should make them a good source for diverse applications in regenerative medicine, but further investigation is needed of their basic biology.

• The Korean Journal of Zoology
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• v.27 no.2
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• pp.73-84
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• 1984

In order to investigate the effect of neurotransmitter on myoblast differentiation in vitro, the effects of dopamine and epinephrine on myoblast fusion and on the intracellular cAMP level in cultured myoblasts were examined. Dopamine $(3\\times10^{-5}M)$ and epinephrine $(3\\times10^{-5}M)$, when added at 34 hr after cell plating, markedly inhibited myoblast fusion, and dopamine was more potent than epinephrine. Both dopamine and epinephrine had no effect on intracellular cAMP level. At the same time, exogeneous dbcAMP, $PGE_1$, and aspirin were used to examine whether cAMP is involved in myoblast differentiation. dbcAMP $(1\\times10^{-4}M)$ inhibited myoblast fusion, whereas $PGE_1 (3\\times10^{-6}M)$ had no inhibitory effect, rather enhancing myoblast fusion. Aspirin, an inhibitor of PG synthetase, was shown to inhibit myoblast fusion. Possible mechanism by which dopamine or epinephrine at a specific concentration used inhibits myoblast fusion is discussed.

• The Journal of Korean Medicine
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• v.32 no.5
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• pp.25-40
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• 2011

Objectives: This study was performed to assess whether herbal medicine and acupuncture before in vitro fertilizationembryo transfer (IVF-ET) is effective on clinical pregnancy. Methods: From May 2010 to January 2011, a prospective analysis study was performed in 38 patients planning to undergo IVF-ET after taking herb medicine and acupuncture treatment. This study investigated the pregnancy rate and analyzed the change of dysmenorrhea by visual analog scale (VAS), body heat and condition of premenstrual syndrome (PMS), vaginal discharge and menstruation status. Results: 1. During herbal medicine and acupuncture treatment, five patients (13.16%) naturally became pregnant and six patients (15.79%) withdrew. After treatment, 15 patients (39.47%) received IVF-ET, 12 patients (31.58%) did not. 2. The biochemical pregnancy rate was 26.67%, the clinical pregnancy rate 26.67%, miscarriage rate 25% and ectopic pregnancy rate was 0%. 3. After treatment, PMS, dysmenorrhea and dysmenorrhea VAS was significantly decreased and the overall menstrual status improved. 4. After treatment, temperature difference of CV17-CV12 and CV4-CV12 increased, but it was not a statistically significant difference. 5. After treatment, decrease of hemoglobin and protein and increase of total bilirubin and creatinine were statistically significant. All the blood test results were within normal levels which proves safety of treatment. Conclusions: This study suggests that herbal medicine and acupuncture treatment before IVF-ET shows similar pregnancy rates with existing rates, but contributes to increasing the possibility of natural pregnancy.

• Macromolecular Research
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• v.16 no.6
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• pp.510-516
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• 2008

New antitumor active polymers, poly(methacryloyl-2-oxy-1,2,3-propanetricarboxylic acid-co-exo-3,6-epoxy-l,2,3,6-tetrahydrophthalic acid) [poly(MTCA-co-ETAc)], poly(methacryloyl-2-oxy-l,2,3-propanetricarboxylic acid-co-hydrogen ethyl-exo-3,6-epoxy-l,2,3,6-tetrahydrophthalate) [poly(MTCA-co-HEET)], and poly(methacryloyl-2-oxy-l,2,3-propanetricarboxylic acid-co-a-ethoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil) [poly(MTCA-co-EETFU)] were synthesized and characterized. Their antitumor activity, inhibition of DNA replication and antiangiogenesis were examined. The structures of the polymers were identified by FT-IR, $^1H$ and $^{13}C$-NMR spectroscopy. The number average molecular weights of the fractionated polymers determined by GPC ranged from 9,400 to 14,900, and polydispersity indices were less than 1.7. The in vitro cytotoxicity of these polymers was determined and their antitumor activity was evaluated. The $IC_{50}$ values (the drug concentration at inhibition of 50% tumor growth) indicated that the synthesized polymers were much better inhibitors of cancer cells and showed lower cytotoxicity than the free 5-FU. The in vivo antitumor activity of the conjugates was examined using mice bearing the sarcoma 180 tumor cell line. The life spans (TIC) of the mice treated with the conjugates were higher than those treated with the free 5-FU. In addition, the synthesized conjugates showed excellent antiangiogenic activity based on an embryo chorioallantoic membrane assay.