• Reproductive and Developmental Biology
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• v.37 no.2
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• pp.85-89
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• 2013

For more than two decades, the intracytoplasmic sperm injection (ICSI) technique has been used as a valuable tool to provide opportunities for studying fertilization, treating human infertility, and producing transgenic animals. Not only in facilitating fertilization but also in propagating mammalian species, ICSI has enhanced the potential of assisted reproductive technologies in human. Polyspermic fertilization has been one of major problems in pig reproduction, but the ICSI helped to solve the problem, and used widely to generate transgenic piglets. Although the ICSI technique is considered to be a very useful tool in assisted reproductive technologies, including generation of transgenic animals, there are some disadvantages using the technique. In this review, we describe the ICSI technique and its application in animal production and human infertility, and discuss advantage and disadvantage of the technique in mammals.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.2
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• pp.142-149
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• 2021

Objective: Bacteriospermia and urogenital infections are common problems in male infertility. This study aimed to evaluate the effects of bacteriospermia on sperm parameters and clinical outcomes in semen samples infected with two common bacteria (Staphylococcus saprophyticus and Escherichia coli) in northern Iran. Methods: Microbiological tests were performed to isolate and identify organisms from 435 semen samples from infertile couples. Semen samples were assessed according to the World Health Organization criteria. The protamine status, chromatin structure, chromatin condensation, and acrosome reaction of sperm and assisted reproductive outcomes were determined in couples with different male infertility factors. Results: Among the total cases, the two most prevalent pathogens were considered: S. saprophyticus (38.2%) and E. coli (52.9%). In the semen samples infected with E. coli, the spontaneous acrosome reaction and abnormal chromatin condensation were more common (p<0.05). Significant increases in abnormal chromatin condensation and deprotamination were seen in the presence of S. saprophyticus. In washed semen, tight adhesion between the sperm midpiece and S. saprophyticus was observed. There was also a significant decrease in the fertilization rate using semen samples infected with S. saprophyticus and E. coli during in vitro fertilization cycles (p<0.001). In addition, the presence of S. saprophyticus and E. coli in semen samples was associated with a lower likelihood of clinical pregnancy in couples with various factors of male infertility. Conclusion: Poor results of assisted reproductive techniques may be correlated with semen samples infected with two common bacteria in northern Iran.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.4
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• pp.368-373
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• 2021

Objective: In this study we aimed to assess anorexigenic peptide levels in patients with or without polycystic ovary syndrome (PCOS) and their effects on assisted reproductive treatment (ART) outcomes. Methods: A prospective case-control study was conducted in a tertiary care university-based ART clinic. Eighty-three patients were included in the study. The PCOS group included 41 patients, and the non-PCOS group included 42 controls. The 2003 Rotterdam criteria were used for PCOS patient selection. The ART indications in the non-PCOS group were tubal factor or unexplained infertility. Venous blood samples were taken on the third day of the menstrual cycle to determine the serum anorexigenic peptide levels. The enzyme-linked immunosorbent assay method was used for laboratory analyses. Results: In the PCOS group, serum obestatin levels were significantly lower than in the control group, but serum anorexigenic peptide levels were similar in PCOS patients with or without clinical pregnancy. Ovarian hyperstimulation syndrome (OHSS) was diagnosed only in PCOS patients, and the obestatin levels of OHSS patients were significantly lower than those of other PCOS patients. Conclusion: Baseline anorexigenic peptide levels did not affect the clinical pregnancy rate in ART cycles. Obestatin may play a role in the pathophysiology of OHSS. This possibility should be confirmed in further research.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.3
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• pp.101-109
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• 2018

In an age when a small quantity of sperm can lead to pregnancy through in vitro fertilization or intracytoplasmic sperm injection, selecting healthy sperm is important. Sperm DNA fragmentation (SDF) is known to be higher in infertile men. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) and the alkaline comet test are SDF tests that directly measure DNA damage and have shown closer correlations with assisted reproduction results than indirect tools such as the sperm chromatin structure assay or the sperm chromatic dispersion test. It is difficult; however, to endorse a single test as the best test overall; instead, it is best to select a testing method based on each patient's clinical condition and goals. In a couple struggling with infertility, if the male partner has a high level of SDF, he should aim to decrease SDF through lifestyle modifications, antioxidant treatment, and ensuring an appropriate duration of abstinence, and physicians need to treat the underlying diseases of such patients. If sperm DNA damage continues despite the patient's and physician's efforts, other methods, such as micromanipulation-based sperm selection or testicular sperm extraction, should be used to select healthy sperm with nuclear DNA integrity.

• BMB Reports
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• v.52 no.8
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• pp.482-489
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• 2019

Reproductive biotechnology has developed rapidly and is now able to overcome many birth difficulties due to infertility or the transmission of genetic diseases. Here we introduce the next generation of assisted reproductive technologies (ART), such as mitochondrial replacement technique (MRT) or genetic correction in eggs with micromanipulation. Further, we suggest that the transmission of genetic information from somatic cells to subsequent generations without gametes should be useful for people who suffer from infertility or genetic diseases. Pluripotent stem cells (PSCs) can be converted into germ cells such as sperm or oocytes in the laboratory. Notably, germ cells derived from nuclear transfer embryonic stem cells (NT-ESCs) or induced pluripotent stem cells (iPSCs) inherit the full parental genome. The most important issue in this technique is the generation of a haploid chromosome from diploid somatic cells. We hereby examine current science and limitations underpinning these important developments and provide recommendations for moving forward.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.2
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• pp.87-92
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• 2022

Objective: The aim of this study was to determine the effects of melatonin and selenium in freezing extenders on frozen-thawed rat sperm. Methods: Semen samples were collected from 20 adult male Wistar albino rats. Following dilution, the samples were divided into six groups: four cryopreserved groups with 1 mM and 0.5 mM melatonin and selenium supplements, and two fresh and cryopreserved control groups. The rapid freezing technique was used to freeze the samples. Flow cytometry was used to assess plasma membrane integrity, mitochondrial membrane potential, and DNA damage, while computer-assisted sperm analysis was used to assess motility. Results: Total motility was higher in the 1 mM melatonin supplementation group than in the cryopreserved control group (mean±standard error of the mean, 69.89±3.05 vs. 59.21±1.31; p≤0.05). The group with 1 mM selenium had the highest plasma membrane integrity (42.35%±1.01%). The cryopreserved group with 0.5 mM selenium had the highest mitochondrial membrane potential, whereas the cryopreserved control group had the lowest (45.92%±4.53% and 39.45%±3.52%, respectively). Conclusion: Cryopreservation of rat semen supplemented with 1 mM melatonin increased sperm motility after freeze-thawing, while supplementation with 0.5 mM selenium increased mitochondrial activity.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.4
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• pp.345-351
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• 2000

Objective: Hatching of the blastocyst from the zona pellucida (ZP) is a key event in mammalian implantation. In vivo, two factors have been identified as possible mediators of hatching: lysis of the ZP by substances elaborated either from the embryo or female reproductive tract and pressure exerted on the zona by expansion of the blastocyst. Two methods of zona manipulation were already in use to enhance the ability of embryos to hatch: mechanical PZD and chemical ZD by acidic Tyrode's solution. But several controversies of each method have been reported. The purpose of this study was to investigate the effect of pronase for mouse embryo hatching. Methods: Mouse embryos were obtained following ovulation induction of $F_1$ animals. Fresh and cryo-thawed morula embryos were exposed to 0.5, 1.0, 2.0, 5.0 ${\mu}g/ml$ pronase in Ham's F10 for 72 hrs. Main outcome measures were the rates of partial hatching and completely hatched blastocysts, and cell number of it. Results: In fresh and cryo-thawed group, the rates of completely hatched blastocyst were significantly higher in 5 ${\mu}g/ml$ pronase treatment group than control group. There was no difference in completely hatched blastocyst total cell number between pronase treatment group and control group. This suggest that pronase treatment did not harmful in mouse embryo development. In pronase treatment group, zona pellucida were thinner than control group. Conclusion: The addition of pronase to culture media may accelerate the hatching of embryo. So, enzymatic treatment of the zona may provide a valuable and effective assisted hatching technique for human in-vitro fertilization-embryo transfer.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.2
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• pp.101-105
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• 1993

This study was carried out to improve pregnancy rate in IVF-ET program through Assisted Hatching (AH) by the use of micromanipulation technique. Among 72 IVF patient, randomized 29 IVF patients were performed for AH by Partial Zona Dissection(PZD). Two to eight cell embryos were micromanipulated just before uterine transfer. The results were as follows: 1. The implantation rates of embryos between PZD group and control group were 10.0%, 4.9%, respectively. 2. The clincal pregnancy rates of both groups were 34.5%,20.9%, respectively. 3. Among 131 PZD embrys, only 2 embryos were damaged mechanically. Although there were no statistical difference in the rates of implantation and pregnancy between PZD group and control group due to small sample size, the PZD group had increasing trend in the rates of implantation and pregnancy. In conclusion, it would be thought that PZD could be adequately used to improve implantation rate and pregnancy rate in IVF-ET program as an assisted technique if much more studies were done. Also the risks resulting from this study can be reduced because of technical stability, which showed the low rate of damaged embryos.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.123-130
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• 1995

Many types of medication regimens have been used for controlled ovarian hyperstimulation for assisted reproductive technique(ART). Questions are now being raised regarding how to lower the escalating costs of assisted reproduction and decrease the extent of patient discomfort and disruption of life style without sacrificing success rates. In this investigation, from January 1994 through August 1994 patients presenting to the Chung-Ang university hospital, infertility clinic were offered the option of the clomiphene citrate (CC)/single Human Menopausal Gonadotropin(HMG) combination and conventional GnRH-agonist combination method. 60 patients (78 cycles) were given CC/single HMG combination as a study group, and 78 patients (102 cycles) were given conventional GnRH-a combined ultrashort protocol as a control group for IVF-ET program and the resulting number of oocyte retrieved, embryo produced, and pregnancy initiated were compared. There were no differences between the two groups in mean age, serum $E_2$, LH and FSH level on menstrual cycle day 2. HMG requirement was 2 ampules in study group and $24.2{\pm}6.8$ ampules in control group. On the day of HCG injection, serum LH and FSH levels were not significantly different, but serum $E_2$, was significantly higher in control group(p<0.001). There was relatively well endometrial quality in control group but not significant compare to study group. In control group, numbers of retrieved oocyte and transferred embryo were significantly more than study group(p<0.001). Fertilization rate was not significantly different in the two groups and pregnancy rates were 20.2% in study group 28.4% in control group(p<0.001). CC/single HMG protocol for IVF-ET is less expensive than GnRH-a combined ultrashort protocol and minimizes patients discomfort. In addition, CC/single HMG protocol produces acceptable pregnancy rate and represents an attractive alternative to select patients undergoing IVF-ET.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.4
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• pp.163-168
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• 2013

Objective: Preimplantation genetic diagnosis (PGD) is an assisted reproductive technique for couples carrying genetic risks. Charcot-Marie-Tooth (CMT) disease is the most common hereditary neuropathy, with a prevalence rate of 1/2,500. In this study, we report on our experience with PGD cycles performed for CMT types 1A and 2F. Methods: Before clinical PGD, we assessed the amplification rate and allele drop-out (ADO) rate of multiplex fluorescent polymerase chain reaction (PCR) followed by fragment analysis or sequencing using single lymphocytes. We performed six cycles of PGD for CMT1A and one cycle for CMT2F. Results: Two duplex and two triplex protocols were developed according to the available markers for each CMT1A couple. Depending on the PCR protocols, the amplification rates and ADO rates ranged from 90.0% to 98.3% and 0.0% to 11.1%, respectively. For CMT2F, the amplification rates and ADO rates were 93.3% and 4.8%, respectively. In case of CMT1A, 60 out of 63 embryos (95.2%) were diagnosed and 13 out of 21 unaffected embryos were transferred in five cycles. Two pregnancies were achieved and three babies were delivered without any complications. In the case of CMT2F, a total of eight embryos were analyzed and diagnosed. Seven embryos were diagnosed as unaffected and four embryos were transferred, resulting in a twin pregnancy. Two healthy babies were delivered. Conclusion: This is the first report of successful pregnancy and delivery after specific PGD for CMT disease in Korea. Our PGD procedure could provide healthy babies to couples with a high risk of transmitting genetic diseases.