• Clinical and Experimental Reproductive Medicine
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• v.25 no.3
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• pp.299-304
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• 1998

Despite the rapid development of assisted reproductive technologies (ART) in recent years, implantation rates after replacement of embryos into the uterine cavity remains low. Several techniques such as culture conditions based on formulations of human tubal fluid and various ART techniques as GIFT, ZIFT, TET have been adopted in recent years to improve embryo viability in vitro and implantation rates. Also, coculture of human IVF-derived embryos have been used in an effort to increase the number of viable embryos following IVF and to improve synchrony between the developing embryo and the uterine environment. The aim of this study was to evaluate whether the use of co culture with autologous cumulus cells has a significant beneficial effect on the development of embryos in vitro and its relation to the pregnancy rates in 120 patients with previous failed IVF-ET from September, 1995 to January 1998. We obtained the results from which significant improvement in the quality of viable embryos were observed using a coculture system with autologous cumulus cells, but pregnancy rates in this group of patients did not differ from the rate in the standard IVF group during the same period. Our study shows that a simplified short-term coculture system with autologous cumulus cells may help rescue moderate quality embryos to cleave regularly.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.4
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• pp.289-298
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• 2023

Complex diseases including cardiovascular disease are caused by a combination of the alternation of many genes and the influence of environments. Recently, non-coding RNAs (ncRNAs) have been shown to be involved in diverse diseases, and the functions of various ncRNAs have been reported. Many researchers have elucidated the mechanisms of action of these ncRNAs at the cellular level prior to in vivo and clinical studies of the diseases. Due to the characteristics of complex diseases involving intercellular crosstalk, it is important to study communication between multiple cells. However, there is a lack of literature summarizing and discussing studies of ncRNAs involved in intercellular crosstalk in cardiovascular diseases. Therefore, this review summarizes recent discoveries in the functional mechanisms of intercellular crosstalk involving ncRNAs, including microRNAs, long non-coding RNAs, and circular RNAs. In addition, the pathophysiological role of ncRNAs in this communication is extensively discussed in various cardiovascular diseases.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.3
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• pp.146-151
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• 2016

Objective: This study was conducted to compare the effects of static culture, dynamic culture, and the combination of dynamic culture with specialized surfaces involving co-culture on human embryonic development. Embryos cultured using conventional static culture (SC) techniques served as a control group. We compared dynamic culture using micro-vibration culture (MVC) and micro-vibration with co-culture (MCoC), in which autologous cumulus cells were used as a specialized surface. Methods: We conducted a chart review of patients who were treated between January 2011 and November 2014 in order to compare embryonic development rates and pregnancy rates among the groups. Zygotes were cultured in micro-droplets, and embryos were subsequently selected for transfer. Some surplus embryos were cryopreserved, and the others were cultured for blastocyst development. A micro-vibrator was set at the frequency of 42 Hz for duration of 5 seconds per 60 minutes to facilitate embryo development. Results: No significant differences among the groups were present in patient's characteristics. However, the clinical pregnancy rates were significantly higher in the MVC group and the MCoC group than in the SC group. No significant differences were found in the blastocyst development rate between the SC group and the MVC group, but the blastocyst development rate in the MCoC group was significantly higher than in the SC and MVC groups. Conclusion: The clinical pregnancy rate was significantly increased by the application of micro-vibration to the embryonic cultures of poor responders. The blastocyst development rate was significantly increased by the application of MCoC to surplus embryos.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.1
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• pp.119-133
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• 1997

In spite of much progress in vitro fertilization and embryo transfer (IVF-ET) program, the pregnancy rate remains at 20-30%, and the endometrial implantation rate per embryo transferred at 10-15%. As a result, about 90% of embryos may fail to implant to the endometrium, and many attempts such as optimization of follicular development, improvement of in vitro culture system including coculture, and micromanipulation of zona pellucida have been made to improve embryonic implantation after IVF-ET. Recently, several procedures of assisted hatching (AH) using micromanipulation have been introduced, and pregnancies and births have been obtained after AH. To develop and establish AH as an effective procedure to improve embryonic implantation, AH with partial zona dissection (PZD) was performed in 116 cycles of 89 infertile couples who had previous repeated failures of standard IVF-ET more than two times (Group I: 71 cycles in 54 patients), or who had implantation failure of embryos with good quality (Group II: 15 cycles in 13), or who had undergone AH without specific indication (Group III: 30 cycles in 22) from January, 1995 to Februry, 1996, and the outcomes of AH were analyzed according to pregnancy rate. The number of oocytes retrieved after controlled ovarian hyperstimulation (COH) was $9.9{\pm}7.1$ in Group I, $11.5{\pm}4.5$ in Group II, and $7.9{\pm}6.4$ in Group III. The number of embryos transferred after AH was $4.7{\pm}1.8$ in Group I, $5.3{\pm}1.3$ in Group II, and $3.5{\pm}2.4$ in Group III. The mean cumulative embryo score (CES) was $56.8{\pm}30.0$ in Group I, $76.1{\pm}35.9$ in Group II, and $38.5{\pm}29.9$ in Group III. The overall clinical pregnancy rate per cycle and per patient was 12.7% (9/71) and 16.7% (9/54) in Group I, 33.3% (5/15) and 38.5% (5/13) in Group II, and 6.7% (2/30) and 9.1% (2/22) in Group III, respectively. There were significant differences in the numbers of oocytes retrieved and embryos transferred, CES, and the clinical pregnancy rate per cycle among three groups. There was a significant inverse correlation between basal serum FSH level and CES, and no pregnancy occurred in patients with CES less than 20. In conclusion, AH of human embryos with PZD prior to ET has improved the implantation and pregnancy rates in IVF-ET patients with the past history of repeated failures, especially in spite of transfer of embryos with good quality, and AH will provide a range of novel techniques which may contribute much to effective management of infertile couples.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.198-203
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• 2007

DNA transfection is a powerful tool for studying gene functions. The $Ca^{2+}$-phosphate precipitation remains one of the most popular and cost-effective transfection techniques. Mature neurons are more resistant to transfection than young ones and most other cell types, and easy to die if microenvironment changes. Here, we report a transfection protocol for mature neurons. The critical modifications are inclusion of glial cells in culture and careful control of $Ca^{2+}$-phosphate precipitation under microscope. Cerebral glial cells were grown until ${\sim}70-80%$ confluence in DMEM/10% horse serum, which was thereafter replaced with serum-free Neurobasal/Ara-C, and 319 hippocampal neurons were plated onto the glial layer Formation of fine $DNA/Ca^{2+}$-phosphate precipitates was induced using Clontech $CalPhos^{TM}$ Mammalian Transfection Kit, and the size ($0.5-1\;{\mu}m$ in diameter) and density(about 10 particles/$100\;{\mu}m^2$) were carefully controlled by the time of incubation in the medium. This modified protocol can be reliably applied for transfection of mature neurons that are maintained longer than two weeks in vitro, resulting in 10-15 healthy transfected neurons per a well of 24-well plates. The efficacy of the protocol was verified by punctate expression of $pEGFP-CaMKII{\alpha}$, a synaptic protein, and diffuse expression of pDsRed2. Our protocol provides a reliable method for transfection of mature neurons in vitro.