Spontaneously hatching human blastocyst is associated with high development potential and live birth rate in vitrified-warmed single blastocyst transfer: A retrospective cohort study.

OBJECTIVE: To investigate the effect of hatching status on predicting pregnancy outcomes in single vitrified-warmed blastocyst transfer (SVBT) by objectively subdividing pre-implantation blastocysts according to hatching status. METHODS: This retrospective study included 817 SVBT cycles performed between January 2016 and December 2017. Transferred embryos were categorized according to their hatching status as follows: group I (n = 147), non-hatching blastocysts; group II (n = 484), hatching blastocysts; and group III (n = 186), completely hatched blastocysts. Hatching blastocysts (group II) were then classified based on the ratio of the blastocystic diameter outside and inside the zona pellucida into early (n = 185), mid- (n = 103), and late (n = 196) hatching stages. Implantation rate (IR), clinical pregnancy rate (CPR), live birth rate (LBR), multiple pregnancy rate (MPR), miscarriage rate, and neonatal outcomes were evaluated. RESULTS: For groups I, II, and III, respectively, the results were as follows: IR (28.6%, 43.6%, and 53.8%; P < 0.001), CPR (27.9%, 42.8%, and 53.2%; P < 0.001), and LBR (23.1%, 32.0%, and 42.5%; P < 0.001). Group III had better IR, CPR, and LBR. Among hatching blastocysts, late-hatching blastocysts had the highest IR (33.5%, 46.6%, and 51.5% for early, mid-, and late hatching, respectively; P = 0.002) and CPR (33.0%, 45.6%, and 50.5%; P = 0.002), with a tendency for a higher rate of LBR. Neonatal outcomes were not influenced by the hatching status. CONCLUSION: Advanced hatching status is positively associated with a higher rate of clinical pregnancy and live birth with no negative effects on neonatal outcomes. Additionally, the quantitative classification of hatching status was found to be predictive of pregnancy outcomes.

RNA sequencing-based transcriptome analysis of granulosa cells from follicular fluid: Genes involved in embryo quality during in vitro fertilization and embryo transfer.

BACKGROUND: Granulosa cells play an important role in folliculogenesis, however, the role of RNA transcripts of granulosa cells in assessing embryo quality remains unclear. Therefore, we aims to investigate that RNA transcripts of granulosa cells be used to assess the probability of the embryonic developmental capacity. METHODS: This prospective cohort study was attempted to figure out the probability of the embryonic developmental capacity using RNA sequencing of granulosa cells. Granulosa cells were collected from 48 samples in good-quality embryo group and 79 in only poor- quality embryo group from women undergoing in vitro fertilization and embryo transfer treatment. Three samples from each group were used for RNA sequencing. RESULTS: 226 differentially expressed genes (DEGs) were related to high developmental competence of embryos. Gene Ontology enrichment analysis indicated that these DEGs were primarily involved in biological processes, molecular functions, and cellular components. Additionally, pathway analysis revealed that these DEGs were enriched in 13 Kyoto Encyclopedia of Genes and Genomes pathways. Reverse transcription quantitative polymerase chain reaction verified the differential expression of the 13 selected DEGs. Among them,10 genes were differently expressed in the poor-quality embryo group compared to good-quality embryo group, including CSF1R, CTSH, SERPINA1, CYP27A1, ITGB2, IL1ß, TNF, TAB1, BCL2A1, and CCL4. CONCLUSIONS: RNA sequencing data provide the support or confute granulosa expressed genes as non-invasive biomarkers for identifying the embryonic developmental capacity.

Clinical Usability of Embryo Development Using a Combined Qualitative and Quantitative Approach in a Single Vitrified-Warmed Blastocyst Transfer: Assessment of Pre-Vitrified Blastocyst Diameter and Post-Warmed Blastocyst Re-Expansion Speed.

Improving the safety and efficacy of assisted reproductive technology programs has been a continuous challenge. Traditionally, morphological grading has been used for embryo selection. However, only a few studies have assessed the morphokinetic variables and morphological dynamics of blastocysts. In the present study, we aimed to perform a quantitative analysis of blastocyst diameter and re-expansion speed. This in-depth morphokinetic evaluation can correlate with currently observed pregnancy outcomes. In total, 658 single vitrified-warmed blastocyst transfer cycles were performed between October 2017 and December 2021, which were divided into four groups according to the pre-vitrified blastocyst diameter. After warming, the groups were subdivided according to the blastocyst re-expansion speed. These quantitative measurements were performed using a time-lapse system. Both diameter and speed are essential in determining the blastocyst quality, while age, day of freezing, and blastocyst quality are crucial from a clinical perspective. The application of both quantitative (diameter and speed) and qualitative (blastocyst quality scores) parameters can help evaluate the clinical usability of blastocysts. This method can prove useful for embryologists in counseling their patients and determining pregnancy patient-oriented strategies.

Effect of phosphodiesterase type 5 inhibitors on sperm motility and acrosome reaction: An in vitro study.

PURPOSE: Phosphodiesterase type 5 (PDE5) inhibitors are effective treatments for erectile dysfunction, and several recent studies have reported positive effects of PDE5 inhibitors on semen parameters as well. However, the data are still controversial. We investigated the effect of PDE5 inhibitors on sperm function by analyzing sperm motility and acrosome reaction. MATERIALS AND METHODS: This study included young healthy men who underwent fertility evaluation; 32 cases were finally included. Men were excluded if they used a PDE5 inhibitor within 2 weeks or if they had insufficient semen volume (≤2 mL), leukocytospermia, or a genitourinary infection. Changes in sperm motility and acrosome reaction were determined after in vitro exposure to the maximal semen concentration of oral intake of sildenafil (100 mg) or tadalafil (20 mg). RESULTS: Mean age of the participants was 35.4±4.9 years, mean sperm concentration was 68.7±32.4 ×106/mL, and mean sperm motility was 50.38%±8.41%. All three groups (control, sildenafil, tadalafil) experienced trends of decreased average sperm motility over time, but these changes were not significant. There were no significant differences between the three groups in the acrosome reaction after 120 minutes of drug exposure, either. The maximal semen concentration of oral intake of sildenafil (100 mg) or tadalafil (20 mg) did not substantially affect sperm motility or acrosome reaction. CONCLUSIONS: Our results suggest that on-demand use of a PDE5 inhibitor is safe and useful for the male partner of an infertile couple; however, further studies are warranted for daily PDE5 inhibitor use.

The Ratio of Mitochondrial DNA to Genomic DNA Copy Number in Cumulus Cell May Serve as a Biomarker of Embryo Quality in IVF Cycles.

Previous studies have reported that the mitochondrial DNA (mtDNA) contents of cumulus cells (CCs) in ovarian follicular fluid are correlated with embryo quality. Quantification of mtDNA CCs has been suggested as a biomarker of embryo viability. The aim of this study was to determine the relationship between mitochondrial DNA (mtDNA)/genomic DNA (gDNA) ratio in CCs and IVF outcomes such as fertilization rates and embryo quality in infertile women. This is an observational study on 144 cumulus-oocyte complexes obtained from 144 patients undergoing IVF-intracytoplasmic sperm injection (ICSI) at a single fertility center. The CCs in ovarian follicular fluid from patients undergoing IVF-ICSI were collected by ovum pick-up. A relative copy number quantification was used to determine mtDNA/gDNA ratio. Quantitative real-time PCR for various markers (ß2M and mtMinArc gene) was used to determine average mtDNA/gDNA ratio of CCs. Investigation of the correlation between mtDNA/gDNA ratio in CCs and IVF outcomes showed no statistically significant correlation between the mtDNA/gDNA ratio in CCs and fertilization rates. However, mtDNA/gDNA ratio and embryo quality showed a statistically significant positive correlation. A significantly higher mtDNA/gDNA ratio was observed in the good quality embryo group compared with the poor quality embryo group (P < 0.05). In addition, the mtDNA/gDNA ratio showed negative correlation with the patient's age (correlation coefficient= -0.228, P < 0.05). Results of this study demonstrate a negative correlation of mtDNA/gDNA ratio in CCs with patient's age, and a low copy number of mtDNA in CCs may have adverse effects on embryo quality in IVF cycles. These results suggest that the ratio of mtDNA/gDNA in CCs may serve as a biomarker in predicting IVF outcomes.

Embryo Selection Based on Morphological Parameters in a Single Vitrified-Warmed Blastocyst Transfer Cycle.

The process of selecting a good quality embryo to improve the pregnancy outcomes is very important. The aim of our study was to elaborate the embryo selection process in a single vitrified-warmed blastocyst transfer (VBT) cycle by analyzing pre-vitrified and post-warmed blastocyst morphological factors to improve pregnancy outcomes. In this retrospective cohort study, we performed 329 single VBT cycles. The pre-vitrified and post-warmed morphological factors of all blastocysts were analyzed. Logistic regression analysis was conducted to select the independent morphological factor associated with ongoing pregnancy. The expansion of blastocoel (mid blastocoel; aOR 2.27, 95% CI.0.80-6.42, p = 0.12, expanded blastocoel; aOR 3.15, 95% CI.1.18-8.44, p = 0.02) in a pre-vitrified blastocyst and the grade of inner cell mass (ICM) (grade B; aOR 0.47, 95% CI.0.27-0.83, p = 0.01, grade C; aOR 0.22, 95% CI 0.09-0.56 p < 0.01) in post-warmed blastocysts significantly predicted the ongoing pregnancy. After fertilization, the embryo developed as a blastocyst on day 5 (day 5) showed a higher ongoing pregnancy than that on day 6 (day 6) (aOR 0.50, 95% CI.0.26-0.94, p = 0.03). The results suggest that while selecting a vitrified-warmed blastocyst in a single VBT cycle, the day 5 vitrified blastocyst should be considered, and a higher expansion grade in the pre-vitrified blastocyst should be selected. Our study has shown that post-warmed ICM grade tends to be a predictive indicator for the selection of the best blastocyst and allows for successful pregnancy, with ongoing pregnancy in a single blastocyst transfer.

The impact of post-warming culture duration on clinical outcomes of vitrified-warmed single blastocyst transfer cycles.

OBJECTIVE: The objective of the study was to compare the effects of long-term and short-term embryo culture to assess whether there is a correlation between culture duration and clinical outcomes. METHODS: Embryos were divided into two study groups depending on whether their post-warming culture period was long-term (20-24 hours) or short-term (2-4 hours). Embryo morphology was analyzed with a time-lapse monitoring device to estimate the appropriate timing and parameters for evaluating embryos with high implantation potency in both groups. Propensity score matching was performed to adjust the confounding factors across groups. The grades of embryos and blastoceles, morphokinetic parameters, implantation rate, and ongoing pregnancy rate were compared. RESULTS: No significant differences were observed in the implantation rate or ongoing pregnancy rate between the two groups (long-term culture group vs. short-term culture group: 56.3% vs. 67.9%, p=0.182; 47.3% vs. 53.6%, p=0.513). After warming, there were more expanded and hatching/hatched blastocysts in the long-term culture group than in the short-term culture group, but there was no significant between-group difference in embryo grade. Regarding pregnancy outcomes, the time to complete blastocyst re-expansion after warming is shorter in women who became pregnant than in those who did not in both culture groups (long-term: 2.19±0.63 vs. 4.11±0.81 hours, p=0.003; short-term: 1.17±0.29 vs. 1.94±0.76 hours, p=0.018, respectively). CONCLUSION: The outcomes of short-term culture and long-term culture were not significantly different in vitrified-warmed blastocyst transfer. Regardless of the post-warming culture time, the degree of blastocyst re-expansion 3-4 hours after warming is an important marker for embryo selection.

Effect of a dual trigger on oocyte maturation in young women with decreased ovarian reserve for the purpose of elective oocyte cryopreservation.

OBJECTIVE: The aim of this study was to determine whether co-administration of a gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin (hCG) for final oocyte maturation improved mature oocyte cryopreservation outcomes in young women with decreased ovarian reserve (DOR) compared with hCG alone. METHODS: Between January 2016 and August 2019, controlled ovarian stimulation (COS) cycles in women (aged ≤35 years, anti-Müllerian hormone [AMH] <1.2 ng/mL) who underwent elective oocyte cryopreservation for fertility preservation were retrospectively analyzed. RESULTS: A total of 76 COS cycles were triggered with a GnRH agonist and hCG (the dual group) or hCG alone (the hCG group). The mean age and serum AMH levels were comparable between the two groups. The duration of stimulation, total dose of follicle-stimulating hormone used, and total number of oocytes retrieved were similar. However, the number of mature oocytes retrieved and the oocyte maturation rate were significantly higher in the dual group than in the hCG group (p=0.010 and p<0.001). After controlling for confounders, the dual-trigger method remained a significant factor related to the number of mature oocytes retrieved (p=0.016). CONCLUSION: We showed improved mature oocyte collection and maturation rate with the dual triggering of oocyte maturation in young women with DOR. A dual trigger appears to be more beneficial than hCG alone in terms of mature oocyte cryopreservation for young women with DOR.

Cryopreserved Human Oocytes and Cord Blood Cells Can Produce Somatic Cell Nuclear Transfer-Derived Pluripotent Stem Cells with a Homozygous HLA Type.

Human pluripotent stem cells (PSCs) through somatic cell nuclear transfer (SCNT) may be an important source for regenerative medicine. The low derivation efficiency of stem cells and the accessibility of human oocytes are the main obstacles to their application. We previously reported that the efficiency of SCNT was increased by overexpression of H3K9me3 demethylase. Here, we applied a modified derivation method to the PSC line and first obtained human SCNT-PSC lines derived from both donated cryopreserved oocytes and cord blood cells with a homozygous human leukocyte antigen (HLA) type. The SCNT-PSCs have very similar characteristics with embryonic stem cells (ESCs) and additionally have shown immunocompatibility in an in vitro and in vivo humanized mouse with a matching HLA type. Our study demonstrates that SCNT technology using donated cryopreserved oocytes and cord blood cells with a known HLA type provides a promising method for establishing a human HLA-matched SCNT-PSC bank for regenerative medicine.

Recovery of ovarian function by human embryonic stem cell-derived mesenchymal stem cells in cisplatin-induced premature ovarian failure in mice.

BACKGROUND: Clinical use of mesenchymal stem cells (MSCs) requires a uniform cell population, and their harvesting is invasive and produces a limited number of cells. Human embryonic stem cell-derived MSCs (hESC-MSCs) can differentiate into three germ layers and possess immunosuppressive effects in vitro. Anticancer treatment is a well-known risk factor for premature ovarian failure (POF). In this study, we investigated the effect of hESC-MSC on recovery of ovarian function in cisplatin-induced POF in mice. METHODS: Female mice received intraperitoneal cisplatin for 10 days. On day 12, CHA15-derived hESC-MSCs were transplanted into the mice by tail vein injection. An injection of PBS served as the negative control. Ovaries were removed 28 days after transplantation for assessment of ovarian histology, immunostaining, and fertility testing by superovulation and in vitro fertilization. hESC-MSC transplantation into mice with cisplatin-induced damage restored body weight and ovary size. RESULTS: Mean primary and primordial follicle counts in the hESC-MSC group were significantly improved compared to the PBS group (P < 0.05), and counts of zona pellucida remnants, an apoptotic sign in ovarian follicles, were significantly reduced (P < 0.05). TUNEL assays and cleaved PARP immunostaining indicated apoptosis, which led to loss of ovarian stromal cells in negative control mice, while Ki-67 was higher in the hESC-MSC group and in non-cisplatin-treated controls than in the PBS group. Ovulation was reduced in the PBS group but recovered significantly in the hESC-MSC group. Rates of blastocyst formation from ovulated eggs and live births per mouse also recovered significantly in the hESC-MSC group. CONCLUSIONS: hESC-MSC restored structure and function in the cisplatin-damaged ovary. Our study provides new insights into the great clinical potential of human hESC-MSC in treating POF.

Clinical and pregnancy outcomes of double and single blastocyst transfers related with morphological grades in vitrified-warmed embryo transfer.

OBJECTIVE: To evaluate clinical and pregnancy outcomes of double and single blastocyst transfers related with morphological grades in vitrified-warmed embryo transfer. MATERIALS AND METHODS: In a retrospective cohort analysis, data were assessed from women who underwent vitrified-warmed blastocyst transfers (VBT) at CHA Gangnam Medical Center between 2014 and 2015. All VBT cycles were categorized into three groups according to blastocyst quality: GG (double good blastocysts transfer), GP (one good and one poor blastocyst transfer), and GS (single good blastocyst transfer). Blastocysts were graded morphologically and ⩾3BB grade was considered good quality. RESULTS: There were 628 transfers in group GG, 401 transfers in group GP, and 277 transfers in group GS. Both clinical pregnancy rate (CPR) and live birth rate (LBR) were the highest in group GG (CPR 65.9%, LBR 55.3%, p < 0.001), but not significantly different between group GP and GS. Multiple pregnancy rates increased significantly in the following order: GS (1.4%), GP (13.5%), and GG (25.6%). Single LBR was the highest in group GS (38.6%, p < 0.001). CONCLUSION: As an effective VBT, especially for reducing multiple pregnancy and increasing single live birth, single good blastocyst transfer may be recommended rather than any double blastocyst transfer methods. Moreover, transferring a good and a poor blastocyst simultaneously should be avoided.

Voltage Dependent N Type Calcium Channel in Mouse Egg Fertilization.

Repetitive changes in the intracellular calcium concentration ([Ca2+]i) triggers egg activation, including cortical granule exocytosis, resumption of second meiosis, block to polyspermy, and initiating embryonic development. [Ca2+]i oscillations that continue for several hours, are required for the early events of egg activation and possibly connected to further development to the blastocyst stage. The sources of Ca2+ ion elevation during [Ca2+]i oscillations are Ca2+ release from endoplasmic reticulum through inositol 1,4,5 tri-phosphate receptor and Ca2+ ion influx through Ca2+ channel on the plasma membrane. Ca2+ channels have been characterized into voltage-dependent Ca2+ channels (VDCCs), ligand-gated Ca2+ channel, and leak-channel. VDCCs expressed on muscle cell or neuron is specified into L, T, N, P, Q, and R type VDCs by their activation threshold or their sensitivity to peptide toxins isolated from cone snails and spiders. The present study was aimed to investigate the localization pattern of N and P/Q type voltage-dependent calcium channels in mouse eggs and the role in fertilization. [Ca2+]i oscillation was observed in a Ca2+ contained medium with sperm factor or adenophostin A injection but disappeared in Ca2+ free medium. Ca2+ influx was decreased by Lat A. N-VDCC specific inhibitor, ω-Conotoxin CVIIA induced abnormal [Ca2+]i oscillation profiles in SrCl2 treatment. N or P/Q type VDC were distributed on the plasma membrane in cortical cluster form, not in the cytoplasm. Ca2+ influx is essential for [Ca2+]i oscillation during mammalian fertilization. This Ca2+ influx might be controlled through the N or P/Q type VDCCs. Abnormal VDCCs expression of eggs could be tested in fertilization failure or low fertilization eggs in subfertility women.

Prematuration Culture with Phosphodiesterase Inhibitors After Vitrification May Induce Recovery of Mitochondrial Activity in Vitrified Mouse Immature Oocytes.

This study investigates the possible causes for low development of blastocysts in vitrified immature oocytes by evaluating the changes of mitochondrial membrane potential and reactive oxygen species (ROS) production and finds a recovery mechanism for these conditions in vitrified immature oocytes. To recover from the cryoinjury, we cultured vitrified immature oocytes in milrinone containing medium for 1, 3, and 5 hours and then extended the culture for oocyte maturation. There was no difference in in vitro maturation and fertilization rate between fresh and vitrified/warmed oocytes. However, the development rate of blastocysts in vitrified/warmed oocytes was significantly lower than that in fresh oocytes (p < 0.05). The development rate of blastocysts was recovered if these oocytes were cultured for 3 hours in milrinone. Vitrified/warmed oocytes incubated in milrinone for 0 and 1 hour showed a significantly higher level of ROS (p < 0.05) and a significantly lower mitochondrial membrane potential (p < 0.05) than fresh oocytes. However, there was no significant difference (p > 0.05) between vitrified oocytes incubated in milrinone for 3 hours and fresh oocytes in terms of ROS level and mitochondrial membrane potential. In conclusion, alteration of highly polarized mitochondria distribution in vitrified oocytes may have an effect on mitochondrial activity, including ROS production during fertilization and further development. Preincubation in milrinone before in vitro maturation of immature vitrified/warmed oocytes may help the redistribution of highly polarized mitochondrial inner membrane potential and in reducing ROS and enhance the further embryonic development after fertilization.

Predictive value of antral follicle count and serum anti-Müllerian hormone: Which is better for live birth prediction in patients aged over 40 with their first IVF treatment?

OBJECTIVE: To evaluate clinical utility of antral follicle count (AFC) and anti-Müllerian hormone (AMH) in predicting in vitro fertilization (IVF) outcomes among the patients over 40 years old in their first IVF cycles. STUDY DESIGN: Total 219 patients aged 40 or older who underwent their first IVF with gonadotropin-releasing hormone antagonist protocol from January 2013 to September 2014 in CHA Gangnam fertility center were retrospectively analyzed. AFC and serum samples were measured prior to IVF treatment. The main outcomes were clinical pregnancy rate and live birth. RESULTS: 36 out of 219 patients achieved clinical pregnancy (16.4%) and 27 out of 219 patients delivered (12.3%). The receiver operating characteristic curve analysis to predict clinical pregnancy showed that both age and AFC equally had higher accuracy by area under the curve (AUC = 0.657, P < 0.01) than serum AMH (AUC 0.613, P = 0.03). The optimum cut-off value of age was ≤41 and that of AFC was >3 to predict clinical pregnancy. For the prediction of live birth, AFC had the highest accuracy (AUC 0.698, P < 0.01), followed by age (AUC 0.674, P < 0.01) and the number of total retrieved oocytes (AUC 0.620, P = 0.02). The optimum cut-off value of age was ≤41, that of AFC was >3 and that of the number of total retrieved oocytes were >6. With multivariate regression analysis, age and AMH were significantly correlated with clinical pregnancy (age, odds ratio [OR] 0.53, P < 0.01; AMH, OR 1.31, P = 0.04), whereas age and AFC were association with live birth significantly (age, OR 0.41, P < 0.01; AFC, OR 1.10, P = 0.02). CONCLUSION: In patients aged over 40, AFC and AMH were shown to be good biomarkers for the prediction of clinical pregnancy and live birth. Although AMH was positively correlated with clinical pregnancy and had no association with live birth, the predictive value of AFC and AMH were similar for both clinical pregnancy and live birth. To predict the live birth, age ≤41, AFC >3 and total retrieved oocytes >6 appeared to be meaningful. This study demonstrated the significance of AMH and AFC as predictors of clinical pregnancy and live birth for old aged women at their first IVF cycle with gonadotropin-releasing hormone antagonist protocol.

Characterization of Tetraploid Somatic Cell Nuclear Transfer-Derived Human Embryonic Stem Cells.

Polyploidy is occurred by the process of endomitosis or cell fusion and usually represent terminally differentiated stage. Their effects on the developmental process were mainly investigated in the amphibian and fishes, and only observed in some rodents as mammalian model. Recently, we have established tetraploidy somatic cell nuclear transfer-derived human embryonic stem cells (SCNT-hESCs) and examined whether it could be available as a research model for the polyploidy cells existed in the human tissues. Two tetraploid hESC lines were artificially acquired by reintroduction of remained 1st polar body during the establishment of SCNT-hESC using MII oocytes obtained from female donors and dermal fibroblasts (DFB) from a 35-year-old adult male. These tetraploid SCNT-hESC lines (CHA-NT1 and CHA-NT3) were identified by the cytogenetic genotyping (91, XXXY,-6, t[2:6] / 92,XXXY,-12,+20) and have shown of indefinite proliferation, but slow speed when compared to euploid SCNT-hESCs. Using the eight Short Tendem Repeat (STR) markers, it was confirmed that both CHA-NT1 and CHA-NT3 lines contain both nuclear and oocyte donor genotypes. These hESCs expressed pluripotency markers and their embryoid bodies (EB) also expressed markers of the three embryonic germ layers and formed teratoma after transplantation into immune deficient mice. This study showed that tetraploidy does not affect the activities of proliferation and differentiation in SCNT-hESC. Therefore, tetraploid hESC lines established after SCNT procedure could be differentiated into various types of cells and could be an useful model for the study of the polyploidy cells in the tissues.

Clinical outcomes of single versus double blastocyst transfer in fresh and vitrified-warmed cycles.

OBJECTIVE: Assisted reproductive technology has been associated with an increase in multiple pregnancies. The most effective strategy for reducing multiple pregnancies is single embryo transfer. Beginning in October 2015, the National Supporting Program for Infertility in South Korea has limited the number of embryos that can be transferred per in vitro fertilization (IVF) cycle depending on the patient's age. However, little is known regarding the effect of age and number of transferred embryos on the clinical outcomes of Korean patients. Thus, this study was performed to evaluate the effect of the number of transferred blastocysts on clinical outcomes. METHODS: This study was carried out in the Fertility Center of CHA Gangnam Medical Center from January 2013 to December 2014. The clinical outcomes of 514 women who underwent the transfer of one or two blastocysts on day 5 after IVF and of 721 women who underwent the transfer of one or two vitrified-warmed blastocysts were analyzed retrospectively. RESULTS: For both fresh and vitrified-warmed cycles, the clinical pregnancy rate and live birth or ongoing pregnancy rate were not significantly different between patients who underwent elective single blastocyst transfer (eSBT) and patients who underwent double blastocyst transfer (DBT), regardless of age. However, the multiple pregnancy rate was significantly lower in the eSBT group than in the DBT group. CONCLUSION: The clinical outcomes of eSBT and DBT were equivalent, but eSBT had a lower risk of multiple pregnancy and is, therefore, the best option.

Associations between malaria and local and global climate variability in five regions in Papua New Guinea.

BACKGROUND: Malaria is a significant public health issue in Papua New Guinea (PNG) as the burden is among the highest in Asia and the Pacific region. Though PNG's vulnerability to climate change and sensitivity of malaria mosquitoes to weather are well-documented, there are few in-depth epidemiological studies conducted on the potential impacts of climate on malaria incidence in the country. METHODS: This study explored what and how local weather and global climate variability impact on malaria incidence in five regions of PNG. Time series methods were applied to evaluate the associations of malaria incidence with weather and climate factors, respectively. Local weather factors including precipitation and temperature and global climate phenomena such as El Niño-Southern Oscillation (ENSO), the ENSO Modoki, the Southern Annular Mode, and the Indian Ocean Dipole were considered in analyses. RESULTS: The results showed that malaria incidence was associated with local weather factors in most regions but at the different lag times and in directions. Meanwhile, there were trends in associations with global climate factors by geographical locations of study sites. CONCLUSIONS: Overall heterogeneous associations suggest the importance of location-specific approaches in PNG not only for further investigations but also public health interventions in repose to the potential impacts arising from climate change.

An efficient SCNT technology for the establishment of personalized and public human pluripotent stem cell banks.

Although three different research groups have reported successful derivations of human somatic cell nuclear transfer-derived embryonic stem cell (SCNT-ESC) lines using fetal, neonatal and adult fibroblasts, the extremely poor development of cloned embryos has hindered its potential applications in regenerative medicine. Recently, however, our group discovered that the severe methylation of lysine 9 in Histone H3 in a human somatic cell genome was a major SCNT reprogramming barrier, and the overexpression of KDM4A, a H3K9me3 demethylase, significantly improved the blastocyst formation of SCNT embryos. In particular, by applying this new approach, we were able to produce multiple SCNT-ES cell lines using oocytes obtained from donors whose eggs previously failed to develop to the blastocyst stage. Moreover, the success rate was closer to 25%, which is comparable to that of IVF embryos, so that our new human SCNT method seems to be a practical approach to establishing a pluripotent stem cell bank for the general public as well as for individual patients. [BMB Reports 2016; 49(4): 197-198].

Histone Demethylase Expression Enhances Human Somatic Cell Nuclear Transfer Efficiency and Promotes Derivation of Pluripotent Stem Cells.

The extremely low efficiency of human embryonic stem cell (hESC) derivation using somatic cell nuclear transfer (SCNT) limits its potential application. Blastocyst formation from human SCNT embryos occurs at a low rate and with only some oocyte donors. We previously showed in mice that reduction of histone H3 lysine 9 trimethylation (H3K9me3) through ectopic expression of the H3K9me3 demethylase Kdm4d greatly improves SCNT embryo development. Here we show that overexpression of a related H3K9me3 demethylase KDM4A improves human SCNT, and that, as in mice, H3K9me3 in the human somatic cell genome is an SCNT reprogramming barrier. Overexpression of KDM4A significantly improves the blastocyst formation rate in human SCNT embryos by facilitating transcriptional reprogramming, allowing efficient derivation of SCNT-derived ESCs using adult Age-related Macular Degeneration (AMD) patient somatic nuclei donors. This conserved mechanistic insight has potential applications for improving SCNT in a variety of contexts, including regenerative medicine.