Search

To explore the relationship between serum 25(OH)D level and pregnancy outcomes (clinical pregnancy rate [CPR] and live birth rate [LBR]) in Chinese women receiving in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)-embryo transfer (ET) (IVF/ICSI-ET).A total of 612 patients included in the study were divided into four cohorts according to serum 25(OH)D with the threshold of 20 ng/ml, 25 ng/ml, 30 ng/ml, and retrospectively analyzed.None of the baseline characteristics of participants was significantly different in the four cohorts except gravid status. The trend of 25(OH)D concentration was positively correlated with CPR and LBR. The younger (age: p 0.001 both in CPR and LBR) women with primary infertility (infertility type: p = 0.004 in LBR) were more likely to get a better pregnancy outcome under the same 25(OH)D concentration stages. As shown on heatmap plots, CPR, and LBR were significantly increased for 25(OH)D concentrations above 30.00 ng/ml and women younger than 30 years old. The adjusted binary logistic regression and restricted cubic spline (RCS) showed that there existed a nonlinear positive correlation between 25(OH)D concentration and pregnancy outcome (CPR and LBR) (PIn Chinese women receiving IVF/ICSI-ET, the serum level of 25(OH)D demonstrated a nonlinear positive correlation with pregnancy outcomes (CPR and LBR), with stronger correlations above 25 ng/ml and worse yields below 30 ng/ml. However, it could not yet be considered different in distinct ages.

Adenine base editors (ABEs) are novel genome-editing tools, and their activity has been greatly enhanced by eight additional mutations, thus named ABE8e. However, elevated catalytic activity was concomitant with frequent generation of bystander mutations. This bystander effect precludes its safe applications required in human gene therapy. To develop next-generation ABEs that are both catalytically efficient and positionally precise, we performed combinatorial engineering of NG-ABE8e. We identify a novel variant (NG-ABE9e), which harbors nine mutations. NG-ABE9e exhibits robust and precise base-editing activity in human cells, with more than 7-fold bystander editing reduction at some sites, compared with NG-ABE8e. To demonstrate its practical utility, we used NG-ABE9e to correct the frequent T17M mutation in Rhodopsin for autosomal dominant retinitis pigmentosa. It reduces bystander editing by ∼4-fold while maintaining comparable efficiency. NG-ABE9e possesses substantially higher activity than NG-ABEmax and significantly lower bystander editing than NG-ABE8e in rice. Therefore, this study provides a versatile and improved adenine base editor for genome editing.

To investigate whether high estrogen (E2) levels caused by controlled ovarian hyperstimulation affect the birth defect rate in singleton assisted reproductive technology (ART) birth after conceived by fresh embryo transfer and frozen embryo transfer (FET).This was a retrospective cohort study. A total of 581 women with singletons, as well as those who have become pregnant and have had an unwanted abortion under high E2 levels on trigger day were divided into three groups. Group A received FET and the E2 levels on trigger day were higher than 5000 pg/ml. Group B received fresh embryo transfer and the E2 levels were between 3000 and 5000 pg/ml. Group C received FET and the E2 levels were between 3000 and 5000 pg/ml.There were no significant differences in birth weight, delivery mode, preterm birth rate, and fetal sex between the three groups (Fresh embryo transfer under supraphysiological level of estrogen exposure may increase the birth defect rate of ART singletons. Even after prenatal screening and diagnosis, a part of birth defect could not be detected during pregnancy. When the estrogen levels on trigger day were no lower than 3000 pg/ml, FET should be advocated to reduce the occurrence of such risk.

CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated endonuclease Cas9) nucleases have been widely applied for genome engineering. Staphylococcus aureus Cas9 (SaCas9) is compact, which can be packaged in AAV (adeno-associated virus) vector for in vivo gene editing. While, wild-type SaCas9 can induce unwanted off-target mutations and substantially limits the applications. So far, there are two reported SaCas9 variants with high-fidelity, including efSaCas9 from our previous study and SaCas9-HF. However, it remains unknown which one possessing the better fidelity and higher activity. Here, we performed a parallel comparison of efSaCas9 and SaCas9-HF in human cells through fluorescent reporter system and target deep sequencing, respectively. The results demonstrated that efSaCas9 possesses higher cleavage activity and fidelity than SaCas9-HF at the most endogenous sites in human cells. Collectively, our study provides insights for the rational selection of suitable SaCas9 for human genome editing.

Background Ovarian hyperstimulation syndrome (OHSS) is a severe disease that can lead to serious complication. Letrozole has been applied during controlled ovarian hyperstimulation (COH) to reduce the rate of OHSS in women undergoing long-term Gonadotropin-releasing Hormone Analog (GnRHa) treatment for assisted fertility. Prednisone can prevent vasodilatation and increased vascular permeability, which is common during OHSS. However, few studies have evaluated the combined effect of letrozole and prednisone in preventing severe OHSS and is the aim of our retrospective study of patients receiving GnRHa treatment. Methods A total of 296 women who accepted autologous in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatments were included in this retrospective study. There were three groups: 146 women had letrozole, including letrozole alone (LE group, n=60) and letrozole with prednisone (LE + Pre group, n=86), and 150 women had no treatment (C group). Severe OHSS was diagnosed according to clinical evidence of hydrothorax, severe dyspnea, oliguria/anuria, and intractable nausea/vomiting. Results The addition of prednisone to letrozole successfully reduced the occurrence rate of severe OHSS than those women administered letrozole alone (55.0% vs. 70.6%, P=0.022). However, the ongoing pregnancy rate was lower in the LE + Pre group than that in the LE-alone group (64.3% vs. 87.0%, P=0.025). Surprisingly, progesterone level on the trigger day (>0.895 ng/mL) is a strong predictor for pregnancy failure with a specificity of 68.3% and sensitivity of 65.7% in the LE-alone group. Conclusions Treatment with a combination of letrozole and prednisone may lower the rate of severe OHSS in women with prolonged gonadotropin-releasing hormone agonist protocol during assisted fertility treatment. When the progesterone level on trigger day is over 0.895 ng/mL, letrozole treatment may negatively affect clinical pregnancy.

Cytosine base editor (CBE) enables targeted C-to-T conversions at single base-pair resolution and thus has potential therapeutic applications in humans. However, the low efficiency of the system limits practical use of this approach. We reported a high-throughput human cells-based reporter system that can be harnessed for quickly measuring editing activity of CBE. Screening of 1813 small-molecule compounds resulted in the identification of Ricolinostat (an HDAC6 inhibitor) that can enhance the efficiency of BE3 in human cells (2.45- to 9.21-fold improvement). Nexturastat A, another HDAC6 inhibitor, could also increase BE3-mediated gene editing by 2.18- to 9.95-fold. Ricolinostat and Nexturastat A also boost base editing activity of the other CBE variants (BE4max, YE1-BE4max, evoAPOBEC1-BE4max and SpRY-CBE4max, up to 8.32-fold). Meanwhile, combined application of BE3 and Ricolinostat led to >3-fold higher efficiency of correcting a pathogenic mutation in ABCA4 gene related to Stargardt disease in human cells. Moreover, we demonstrated that our strategy could be applied for efficient generation of mouse models through direct zygote injection and base editing in primary human T cells. Our study provides a new strategy to improve the activity and specificity of CBE in human cells. Ricolinostat and Nexturastat A augment the effectiveness and applicability of CBE.

Research questionTo explore the relationship between serum 25(OH)D level and Clinical Pregnancy Rate (CPR) as well as Live Birth Rate (LBR) in Chinese women receiving IVF/ICSI-ET.DesignThe data of 612 patients who underwent IVF/ICSI-ET in the Reproduction Center of the Second Affiliated Hospital of Wenzhou Medical University were retrospectively analyzed. ResultsNone of the baseline characteristics of participants were significantly different between the two cohorts. The trend of 25(OH)D concentration was positively correlated with CPR and LBR. Moreover, our results indicated that the younger (Age: pp=0.004 in LBR) were more likely to get a better pregnancy outcome under the same 25(OH)D concentration stages. As shown on heatmap plots, CPR and LBR were significantly increased for 25(OH)D concentrations above 30.00ng/ml and women younger than 30 years old. The adjusted binary logistic regression and RCS showed that there exists a nonlinear positive correlation between 25(OH)D concentration and pregnancy outcome (CPR and LBR) (nonlinear < 0.001, respectively). The women with a sufficient 25(OH)D concentration (30ng/ml) had 1.07 (clinical pregnancy) and 1.05 (live birth) times higher successful birth outcomes compared to women with an insufficient 25(OH)D concentration (25ng/ml). (OR25ng/ml,ref=30ng/ml [95%CI] = 0.935[0.932-0.938] and 0.947[0.945-0.950],PConclusionIn Chinese women receiving IVF/ICSI-ET, the serum level of 25(OH)D demonstrated a non-linear positive correlation with pregnancy outcome（CPR&LBR, with stronger correlations above 25 ng/ml and worse yields below 30 ng/ml. However, it could not yet be considered different in distinct ages.

IntroductionMorphological evaluation is used to select embryos for in vitro fertilisation. However, it does not fully reflect the implantation potential. Preimplantation genetic testing for aneuploidies (PGT-A) can detect embryonic aneuploidy, but biopsy procedure is invasive. Currently, a non-invasive PGT (ni-PGT) approach using spent medium is being evaluated. However, the clinical benefit of ni-PGT has not been clearly demonstrated. A multicentre randomised trial is needed to verify whether ni-PGT can be an new effective tool for evaluating embryos.Methods and analysisOverall, 1148 couples aged 35~42 (women) receiving in vitro fertilization–intracytoplasmic sperm injection are planned to be enrolled. Couples will be digitally randomised to (1) ni-PGT and (2) conventional morphology groups at a 1:1 treatment ratio. The primary outcome will be the ongoing pregnancy rate related to the first transfer cycle within 6 months after oocyte retrieval.Ethics and disseminationThe study protocol is approved by the Ethics Committee of Peking University Third Hospital and the participating hospitals. The results will be disseminated through international conferences and scientific journals.Trial registration numberNCT04339166.

The CRISPR (clustered regularly interspaced short palindromic repeat)-Cas (CRISPR-associated) nucleases have been widely applied for genome engineering. Cas9 (Streptococcus pyogenes Cas9 [SpCas9] and Staphylococcus aureus Cas9 [SaCas9]) and Cpf1 (i.e., Francisella novicida U112 Cpf1 [FnCpf1], also named FnCas12a) were harnessed to perform gene editing in human cells. Precise genetic modification by homology-directed repair (HDR) is an attractive approach for in situ gene correction. However, so far, the comparative efficiencies of HDR mediated by different CRISPR orthologs remain unknown. To address this question, in this study, we developed a reporter system to investigate HDR efficiencies triggered by various CRISPR orthologs. We found that SpCas9 and SaCas9, the two most commonly used Cas9 enzymes, possessed a similar ability to induce HDR. Interestingly, with the increasing amount of coding plasmids or additional nuclear localization sequences, FnCpf1 could improve the HDR efficacy. Collectively, our study provides insights for the rational selection of appropriate tools for human genome manipulation.

Since the reproductive toxicity of COVID-19 vaccines have not been assessed in previous clinical trials, and studies have shown that SARS-CoV-2 is associated with a decrease in sperm parameters. Although it has been reported that the mRNA SARS-CoV-2 vaccines do not adversely affect semen parameters, whether this conclusion applies to inactivated vaccines remains unclear. Here, we conducted a study among patients who accepted in vitro fertilization (IVF) at the reproductive centre between June and August of 2021. In the enrolled cases, men who have completed two doses of COVID-19 inactivated vaccine were included in "vaccine group" (N = 105), and those who were not vaccinated were included in "control group" (N = 155). In this study, we compare the sperm parameters and embryo quality between these two groups. Our data showed that the sperm parameters were similar in terms of volume, sperm concentration, sperm count, progressive motility, total motility and total motile sperm count between these two groups. Similarly, no significant differences were observed in IVF outcomes. The mean number of 2PN, cleavage-stage embryos, blastocysts, and good-quality blastocysts was 8.59 ± 4.47, 5.06 ± 3.17 and 2.08 ± 1.79 in vaccine group, 7.75 ± 4.14, 4.34 ± 3.06 and 1.74 ± 1.54 in control group, respectively. The high-quality blastocyst rate was 41.05% (218 of 531) in vaccine group and 40.03% (269 of 672) in control group (p 0.05). In addition, no differences were observed in biochemical and clinical pregnancy rates between the two groups. In summary, our results revealed that COVID-19 inactivated vaccine administration exhibited no negative effect on sperm parameters and embryo quality in IVF.

Background. Deficient spermatozoon motility is one of the main causes of male infertility. However, there are still no accurate and effective treatments in a clinical setting for male asthenospermia. Exploring the genes and mechanism of asthenospermia has become one of the hot topics in reproductive medicine. Our aim is to study the effect of SLRIP on human spermatozoon motility and oxidative stress. Methods. Sperm samples were collected including a normospermia group (60 cases) and an asthenospermia group (50 cases). SLIRP protein expression in spermatozoa was examined by western blotting, and relative mRNA expression of SLIRP in spermatozoa was quantified by reverse transcription polymerase chain reaction. Levels of reactive oxygen species (ROS), adenosine triphosphate (ATP) content, and the activity of manganese superoxide dismutase (MnSOD) in spermatozoa were also measured. Results. The mRNA level and protein expression of SLIRP in the asthenospermia group were significantly reduced compared with those in the normospermia group. The ROS active oxygen level in the asthenospermia group significantly increased; however, the ATP content decreased significantly as well as the activity of MnSOD. Conclusion. SLIRP regulates human male fertility, and SLIRP and sperm progressive motility are positively correlated. The expression of SLIRP is declined, oxidative damage is increased, and energy metabolism is decreased in spermatozoa of asthenospermia patients compared to normospermia participants.

Base editing is a form of genome editing that can directly convert a single base (C or A) to another base (T or G), which is of great potential in biomedical applications. The broad application of base editing is limited by its low activity and specificity, which still needs to be resolved. To address this, a simple and quick method for the determination of its activity/specificity is highly desired. Here, we developed a novel system, which could be harnessed for quick detection of editing activity and specificity of base editors (BEs) in human cells. Specifically, multiple cloning sites (MCS) were inserted into the human genome via lentivirus, and base editing targeting the MCS was performed with BEs. The base editing activities were assessed by specific restriction enzymes. The whole process only includes nucleotide-based targeting the MCS, editing, PCR, and digestion, thus, we named it NOTEPAD. This straightforward approach could be easily accessed by molecular biology laboratories. With this method, we could easily determine the BEs editing efficiency and pattern. The results revealed that BEs triggered more off-target effects in the genome than on plasmids including genomic indels (insertions and deletions). We found that ABEs (adenine base editors) had better fidelity than CBEs (cytosine base editors). Our system could be harnessed as a base editing assessment platform, which would pave the way for the development of next-generation BEs.

To investigate the feasibility of switching from in vitro fertilization (IVF) to in vitro maturation (IVM) combined with all-blastocyst-culture and transfer as a supplementary infertility treatment in patients with ovarian hyperstimulation syndrome (OHSS) tendency METHODS: Retrospective cohort study including 184 patients who switched from IVF and underwent 192 IVM cycles between January 2016 and December 2020. The outcomes were compared between cleavage-stage embryo transfer (group A, n = 74) and blastocyst-stage transfer (group B, n = 52) groups.The OHSS rate is 0%. 66 cycles were canceled for transfer. Among the 126 transfer cycles, number of retrieved oocytes, proportion of metaphase II oocytes, cleavage rate, and proportion of high-quality embryos on day 3 post-fertilization are significantly lower in group A than that in group B. On the contrary, number of transferred embryos is significantly lower in group B than that in group A, whereas the rates of implantation, clinical pregnancy, and live births are significantly higher in group B than that in group A.Timely switching to IVM combined with all-blastocyst-culture and transfer for patients undergoing controlled ovarian hyperstimulation and exhibiting characteristics of OHSS tendency is feasible as a supplementary infertility treatment.

The purpose of this study was to explore the influence of decreased serum estradiol (The clinical data of 300 IVF-ET cycles with patients were analyzed retrospectively. According to the presence of fallingDuration and total dosage of gonadotropin (Gn) used were statistically more in group A than in group B (Reduction of

Objective. The purpose of this study was to explore the influence of decreased serum estradiol (E2) levels during controlled ovarian hyperstimulation (COH) on in vitro fertilization and embryo transfer (IVF). Methods. The clinical data of 300 IVF-ET cycles with patients were analyzed retrospectively. According to the presence of falling E2 level during the COH, we divided all subjects into two groups: the E2 levels fall group (n = 120, group A) and the control group (n = 180, group B). In group A, there were 57 patients with falling E2 with drug dosage reduction. The other 63 patients experienced the decreased E2 level spontaneously. The clinical and laboratory variables in the groups were compared. Receiver operator characteristic (ROC) curve analyses were carried out in order to evaluate the predict value of E2 level on the day of human chorionic gonadotropin (hCG) administration on IVF outcomes. Results. Duration and total dosage of gonadotropin (Gn) used were statistically more in group A than in group B ( P P = 0.048). Women in group A had lower clinical pregnancy rate ( P = 0.029), live birth rate ( P P = 0.001), and higher early abortion rates ( P = 0.008) than group B. Women with spontaneously falling E2 group had a higher BMI index than those in the drug dosage reduction group ( P = 0.001). More dosage and longer duration of Gn in spontaneously falling E2 group than in the drug dosage reduction group ( P 2020 pg/ml on the hCG day might be an index to predict live birth. The sensitivity was 57.0% and the specificity was 61.7%. Conclusions. Reduction of E2 during COH might adversely affect the clinical pregnancy, early abortion, and ongoing pregnancy of IVF-ET.

Clinical and genetic characteristics of ELANE mutation of a 3-year-old male who had a severe congenital neutropenia (SCN) were examined. We then investigated whether CRISPR/Cas9-mediated gene editing could correct the mutation.The proband underwent extensive clinical assessments, such as exome sequencing and bioinformatics analysis, so that pathogenic genes could be identified. Sanger sequencing was also utilized for confirmation. The cell line, 293-ELANE, harboring ELANE mutation was generated, and the mutation was then corrected by CRISPR/Cas9-mediated homology-directed repair (HDR).The ELANE gene test in the proband unveiled a heterozygous de novo missense mutation: c. 248T A (p.V83D), which was not detected in his asymptomatic parents who had provided peripheral blood samples. We found that 46.01% of his father's sperm cells had the same mutation. These results demonstrate that the proband inherited the ELANE mutation from his father, who had an average neutrophil count but had a germline mosaicism. The highest repair efficiency of CRISPR/Cas9-mediated HDR for 293-ELANE is 4.43%.We identified a missense mutation (p.V83D) in ELANE that causes SCN. This is the first report on paternal semen mosaicism of an ELANE mutation. Our study paves the way for preimplantation genetic diagnosis (PGD) based on ELANE mutation prevention and clinical treatment of congenital disabilities.

BACKGROUND: The long protocol has been recognized as the gold standard in controlled ovarian hyperstimulation (COH). However, the full dose of gonadotropin-releasing hormone agonist (GnRH-a) under the prolonged protocol has become increasingly popular in China. This study sought to compare pregnancy outcomes among the following 3 groups: a long protocol group, and 2 types of improved prolonged protocol groups. METHODS: A retrospective cohort study was conducted of 550 patients undergoing fresh embryo transfer (ET). Patients were treated either with the improved prolonged protocol in the follicular phase (Group 1; n=288) or the mid-luteal phase (Group 2; n=143), or the long protocol (Group 3; n=119). The clinical and laboratory outcomes of the 3 groups were compared. RESULTS: The general characteristics of the women in the 3 groups were comparable. On the day on which gonadotropin (Gn) was first administered and on the day on which human chorionic gonadotropin (hCG) was administered, the luteinizing hormone (LH) levels of patients in both Groups 1 and 2 were lower than those of patients in Group 3. The number of oocytes retrieved, fertilized, and cleaved, and the number of high-quality embryos in the 3 procedures were similar. However, the number of transferred embryos, the rate of blastocyst progression, and the rate of implantation differed. The clinical pregnancy rates (CPRs)were significantly higher in the prolonged protocol groups (62.5% and 61.5%) than the long protocol group (48.7%). Further, statistically significant differences in the live-birth rates (LBRs) (56.9% vs. 57.3% vs. 42.9%) were observed. However, no differences in early abortion rates were found. CONCLUSIONS: As a result of pituitary downregulation with GnRH-a, the prolonged groups had better CPRs and LBRs than the long protocol group. The prolonged protocol in the mid-luteal phase was equally effective as that in the early follicular phase in fresh in-vitro fertilization (IVF)/intracytoplasmic sperm injection-embryo transfer (ICSI-ET) cycles. High LH levels on the day of hCG may be a predictor of adverse clinical outcomes.

Objective To investigate transfer strategies in the frozen-thawed embryo transfer (FET) cycle. Methods The clinical data of 1,652 FET patients were divided into five groups according to the number and quality of the transferred blastocyst: high-quality single blastocyst group (group A, n = 558), high-quality plus poor-quality double blastocyst group (group B, n = 435), poor-quality double blastocyst group (group C, n = 241), high-quality double blastocyst group (group D, n = 298), and poor-quality single blastocyst group (group E, n = 120). Inter-group comparison analyses of primary conditions, pregnancy outcomes and neonatal outcomes were then performed. Results Group A had the highest embryo implantation rate (67.38%), significantly different from the implantation rates of the other four groups. The gemellary pregnancy rate (1.60%), preterm birth rate (5.58%), neonatal birth weight (3,350g [3,000g, 3,650g]), neonatal birth age (39.57 weeks [38.71, 40.34]), and incidence of low birth weight (7.02%) in group A were different from those in groups B, C, and D, but did not significantly differ from those in group E. Moreover, the proportions of male infants born in groups A (56.86%) and D (59.41%) were significantly higher than those in the other three groups. Double blastocyst transfer (0.528, 95% CI [0.410–0.680], P P = 0.001) were found to be protective factors for live birth. In addition, double blastocyst transfer was also the largest risk factor for pregnancy complications (3.120, 95% CI [2.323–4.190], P P P P Conclusion The live birth rate of frozen-thawed high-quality single blastocyst transfer is lower than that of double high-quality blastocyst transfer, which can significantly increase the embryo implantation rate. High-quality single blastocyst transfer also significantly lowers the risk of gemellary pregnancy, preterm birth, and low birth weight, and can significantly improve maternal and infant outcomes. After weighing the pros and cons of live birth with pregnancy and neonatal complications, the authors believe that high-quality single blastocyst transfer is the optimal FET strategy for young women and is worthy of further clinical application. Despite this recommendation, high-quality single blastocyst transfer can increase the risk of monozygotic twins, as well as significantly increase the proportion of male infants born.

BackgroundIt is commonly believed that using frozen sperms after TESA was effective for OA patients. Nevertheless, scholars are worried about the prognosis of ICSI with frozen testicular sperm. In this study, we aim to compare the pregnancy and neonatal outcomes of ICSI using cryopreserved versus fresh spermatozoa collected by TESA.MethodsA total of 317 cases of OA patients treated with ICSI in a university affiliated hospital from January 2016 to December 2020 were included in this retrospective study, and they were divided into two groups according to the sperm used for ICSI: Frozen sperm group (N=154) and Fresh sperm group(N=163). The outcomes were measured by the following indicators: Two pronucleus (2PN) fertilization rate, 2PN cleavage rate, high-quality blastocyst rate, average number of embryos transferred, implantation rate, clinical pregnancy rate, multiple pregnancy rate, miscarriage rate, preterm birth rate, live birth rate (LBR) , sex ratio at birth (male) and average newborn birth weight.ResultsThe present data showed no statistically significant difference in 2PN fertilization rates, 2PN cleavage rates, high-quality blastocyst rates and the average number of embryos transferred in the two groups. Similarly, no difference was found in implantation rate, clinical pregnancy rate, multiple pregnancy rate, miscarriage rate, premature delivery rate, LBR and sex ratio at birth (P>0.05). The average newborn birth weight was similar in the two groups (2932.61±728.40 vs 3100.32±515.64) (P>0.05), but there was a higher incidence of Low-Birth-Weight newborn in the frozen group (20.91% vs 8.49%)(PConclusionsAs for men with obstructive azoospermia, the use of frozen testicular sperm by TESA was efficient. There was a similar pregnancy outcome of ICSI using frozen or fresh spermatozoa collected by TESA. However, it may lead to higher incidence of newborns of low birth weight, which needs further research based on larger samples.

Clustered regularly interspaced short palindromic repeats and associated proteins (CRISPR-Cas) of bacterial adaptive immunity have been adopted as a powerful and versatile tool for manipulation of the genome. This paradigm has been widely applied in biological research and treatments of animal or cellular disease models. A critical feature of CRISPR-Cas is the protospacer adjacent motif (PAM), which dictates the DNA target recognition mechanism of Cas proteins. While, direct identifying functional PAM sequences in human cells remains a challenge. Here, we developed a positive screen system termed PAM-DOSE (PAM Definition by Observable Sequence Excision) to delineate the functional PAMs in human cells. Specifically, the PAM libraries for CRISPR-Cas (SpCas9, SpCas9-NG, FnCas12a, AsCas12a, LbCas12a and MbCas12a) were generated and the corresponding CRISPR-Cas mediated cleaved fragments with functional PAM in human cells were harvested for DNA sequencing, which could be tracked and visualized with either florescence microscopy or flow cytometry analysis. With this system, we identified the functional PAMs of CRISPR-Cas members. We also found that spacer sequence affects the PAM preference of Cas proteins. This method will facilitate identification of functional PAMs for Cas-mediated human genome editing applications. Keywords: CRISPR-Cas, PAM, Human, Next-generation Sequencing

Background: Assisted reproductive techniques (ART) have been extensively used to treat infertility. Inaccurate prediction of a couple’s fertility often leads to lowered self-esteem for patients seeking ART treatment and causes fertility distress. Objective: This prospective study aimed to statistically analyze patient data from a single reproductive medical center over a period of 18 months, and to establish mathematical models that might facilitate accurate prediction of successful pregnancy when ART are used. Methods: In the present study, we analyzed clinical data prospectively collected from 760 infertile patients visiting the second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University between June 1, 2016 and December 31, 2017. Various advanced statistical methods, including broken-line regression, were employed to analyze the data. Results: Age remained the most important factor affecting the outcome of IVF/ICSI. Using the broken-line regression model, the fastest clinical pregnancy declining age was between 25 and 32. Female infertility type was found to be a key predictor for the number of good-quality embryos and successful pregnancy, along with the antral follicle count (AFC), total number of embryos, recombinant follicle stimulating hormones (rFSH) dosage, estradiol (E2) on the trigger day, and total number of oocytes retrieved. rFSH dosage was also significantly associated with the number of oocytes retrieved and the number of frozen embryos. Conclusion: The fastest clinical pregnancy declining age is ranged between 25 and 32, and female infertility type is evidenced as another key predictive factor for the cumulative outcome of ART.

To analyze the effects of blastocysts on the 5th day (D5) and 6th day (D6) of frozen–thawed blastocyst transplantation on pregnancy outcome and provide evidence for further improvement of the strategy. This study included transfers from the Reproductive Medicine Center of the Second Affiliated Hospital of Wenzhou Medical University during freeze–thaw cycles from January 2016 to December 2017. They were divided into D5 group (1616 cases) and D6 group (619 cases) according to blastocyst formation and development. Each group was further divided into 5 groups according to the quality of the blastocyst and the number of transplants, making a total of 10 groups. Following the frozen transplantation cycle, the transplanting rate was significantly higher for D5 (41.73%) than for D6 (23.98%) (P < 0.05); the ongoing pregnancy rate (47,40%) was also significantly higher than that of D6 (28.43%) (P < 0.05).In the frozen–thawed blastocyst resuscitation transplantation, compared to D6 blastocysts, D5 blastocysts were more conducive to blastocyst implantation and could be used to achieve better clinical pregnancy outcome. In blastocyst selection, a single D5 excellent blastocyst transplant is preferred. Only at the 6th day of non-excellent D6, 2 blastocysts are recommended for transplantation.

Leydig cells (LCs) play crucial roles in producing testosterone, which is critical in the regulation of male reproduction and development. Low levels of testosterone will lead to male hypogonadism. LC transplantation is a promising alternative therapy for male hypogonadism. However, the source of LCs limits this strategy for clinical applications. Thus far, others have reported that LCs can be derived from stem cells by gene transfection, but the safe and effective induction method has not yet been reported. Here, we report that Leydig-like cells can be derived from human induced pluripotent stem cells (iPSCs) using a novel differentiation protocol based on molecular compounds. The iPSCs-derived Leydig-like cells (iPSC-LCs) acquired testosterone synthesis capabilities, had the similar gene expression profiles with LCs, and positively expressed Leydig cell lineage-specific protein markers LHCGR, STAR, SCARB1, SF-1, CYP11A1, HSD3B1, and HSD17B3 as well as negatively expressed iPSC-specific markers NANOG, OCT4, and SOX2. When iPSC-LCs labeled with lipophilic red dye (PKH26) were transplanted into rat testes that were selectively eliminated endogenous LCs using EDS (75 mg/kg), the transplanted iPSC-LCs could survive and function in the interstitium of testes, and accelerate the recovery of serum testosterone levels and testis weights. Collectively, these findings demonstrated that the iPSCs were able to be differentiated into Leydig-like cells by few defined molecular compounds, which may lay the safer groundwork for further clinical application of iPSC-LCs for hypogonadism.

Summary Background Elective single embryo transfer (eSET) has been increasingly advocated, but concerns about the lower pregnancy rate after reducing the number of embryos transferred have encouraged transfer of multiple embryos. Extended embryo culture combined with electively freezing all embryos and undertaking a deferred frozen embryo transfer might increase pregnancy rate after eSET. We aimed to establish whether elective frozen single blastocyst transfer improved singleton livebirth rate compared with fresh single blastocyst transfer. Methods This multicentre, non-blinded, randomised controlled trial was undertaken in 21 academic fertility centres in China. 1650 women with regular menstrual cycles undergoing their first cycle of in-vitro fertilisation were enrolled from Aug 1, 2016, to June 3, 2017. Eligible women were randomly assigned to either fresh or frozen single blastocyst transfer. The randomisation sequence was computer generated, with block sizes of two, four, or six, stratified by study site. For those assigned to frozen blastocyst transfer, all blastocysts were cryopreserved and a delayed frozen-thawed single blastocyst transfer was done. The primary outcome was singleton livebirth rate. Analysis was by intention to treat. This trial is registered at the Chinese Clinical Trial Registry, number ChiCTR-IOR-14005405. Findings 825 women were assigned to each group and included in analyses. Frozen single blastocyst transfer resulted in higher rates of singleton livebirth than did fresh single blastocyst transfer (416 [50%] vs 329 [40%]; relative risk [RR] 1·26, 95% CI 1·14–1·41, p vs nine of 825 [1·1%] in fresh single blastocyst transfer; p=0·16), pregnancy loss (134 of 583 [23·0%] vs 124 of 481 [25·8%]; p=0·29), other obstetric complications, and neonatal morbidity were similar between the two groups. Frozen single blastocyst transfer was associated with a higher risk of pre-eclampsia (16 of 512 [3·1%] vs four of 401 [1·0%]; RR 3·13, 95% CI 1·06–9·30, p=0·029). Interpretation Frozen single blastocyst transfer resulted in a higher singleton livebirth rate than did fresh single blastocyst transfer in ovulatory women with good prognosis. The increased risk of pre-eclampsia after frozen blastocyst transfer warrants further studies. Funding The National Key Research and Development Program of China.

Ruqing Yang,1 Minghua Jiang,2 Junzhao Zhao,1 Hui Chen,2 Jian Gong,2 Yaying You,3 Laiyue Song,3 Zhen Li,4 Qian Li2 1Reproductive Medicine Center, Department of Gynaecology and Obstetrics, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China; 2Department of Clinical Laboratory, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China; 3The Second Clinical Medical College, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China; 4Department of Traditional Chinese Medicine, The Third Affiliated Hospital of Guangzhou Medical University, Key Laboratory for Major Obstetric Diseases of Guangdong Province, Guangzhou, Guangdong 510150, China Background: Near-triploidy/tetraploidy is rarely found in acute leukemia. Only limited data are available to characterize this condition, and it remains largely unknown. Patients and methods: In our study, we performed karyotype analysis on 1,031 patients diagnosed with acute leukemia from 2006 to 2018. A total of 10 patients of near-triploidy/tetraploidy karyotype were enrolled. Two cases of near-triploidy (66–79 chromosomes) and eight cases of near-tetraploidy (84–100 chromosomes) were identified. Bone marrow samples of these 10 patients were analyzed by fluorescence in situ hybridization with 19 commercially available probes that detected a small portion of gene alterations and large regions of chromosome amplifications. Results: Of the six patients with acute myelocytic leukemia, we detected three cases of double t(8;21)(q22;q22) that have not been previously reported, and one of them demonstrated ins(21;8)(q22;q24q22). We also describe a novel pediatric case carrying double t(15;17)(q22;q21) and receiving targeted treatment with all-trans retinoic acid therapy. To date, this case has responded well to the regimen and has shown continuous complete remission. All patients received chemotherapy. One of them received allogeneic hematopoietic stem cell transplant (HSCT) and survived for 22 months. Eight of the 10 patients died, and the median overall survival was 11 months. Conclusion: Using fluorescence in situ hybridization, we identified the distinct complex karyotype of near-triploidy/tetraploidy and provided further prognostic information. Tetraploidy acute promyelocytic leukemia had favorable prognosis; thus, HSCT was not necessary. The case of insertion t(21;8)(q22;q24q22) in tetraploidy responded poorly to chemotherapy and achieved molecular remission with difficultly. Data from patients in this group indicated that near-triploidy/tetraploidy acute leukemia has poor prognosis and new therapy is urgently needed. Keywords: near-triploidy, tetraploidy karyotype, acute leukemia, fluorescence in situ hybridization, gene

BACKGROUND The aim of this study was to evaluate the efficacy of specific in vitro fertilization (IVF) protocols for patients with polycystic ovary syndrome (PCOS), and therefore, analyze the first-rank intention IVF protocol. MATERIAL AND METHODS In this study, 408 PCOS patients (464 treatment cycles) were enrolled and assigned to one of 3 groups: group 1 [oral contraceptive long-term regimen group (OC-L protocol group, n=91)], group 2 (GnRH antagonist protocol, n=80), and group 3 [follicular phase long-term regimen group, C₁-L protocol group n=293]. The endpoints are the number of eggs, oocyte maturation rate, high-quality embryo rate and clinical pregnancy rate after fresh embryos transfer, the incidence of ovarian hyperstimulation syndrome and abortion rate. RESULTS The number of eggs, oocyte maturation rate, and high-quality embryo rate in the C₁-L protocol group were significantly higher than those in the other 2 groups. The fertilization rate and cleavage rate of the 3 groups were not significantly different. After fresh embryo transplantation, the pregnancy rate of C₁-L protocol group was significantly higher than that of the other groups. CONCLUSIONS This study showed that the super-long downregulation in follicular phase regimen has advantages of simple treatment process, high oocyte maturation rate, high quality embryo rate, and pregnancy rate. It is a good choice for PCOS patients to promote ovulation during IVF.

Cas12a-mediated targeted genome engineering strategies have enabled a broad range of research and clinical applications. However, the limited target-selection spectrum and low activity/fidelity remain a bottleneck for its widespread application in precision site-specific human genome editing. Therefore, there exists an acute need to identify novel Cas12a nucleases with improved features for genome editing. By screening a range of candidate Cas12a nucleases, here we demonstrate that Lb2Cas12a possesses genome editing activity in human cells and it has greater flexibility in PAM (5'-BYYV-3') selection. Furthermore, we engineered Lb2Cas12a to generate variants (Lb2Cas12a-RVR and Lb2Cas12a-RR), which greatly expands the target-selection spectrum. Our study illustrated that Lb2Cas12a could be harnessed as additional genome editing tool for the manipulation of human genome.

Clustered regularly interspaced short palindromic repeat–Cas12a has been harnessed to manipulate the human genome; however, low cleavage efficiency and stringent protospacer adjacent motif hinder the use of Cas12a-based therapy and applications. Here, we have described a directional evolving and screening system in human cells to identify novel FnCas12a variants with high activity. By using this system, we identified IV-79 (enhanced activity FnCas12a, eaFnCas12a), which possessed higher DNA cleavage activity than WT FnCas12a. Furthermore, to widen the target selection spectrum, eaFnCas12a was engineered through site-directed mutagenesis. eaFnCas12a and one engineered variant (eaFnCas12a-RR), used for correcting human RS1 mutation responsible for X-linked retinoschisis, had a 3.28- to 4.04-fold improved activity compared with WT. Collectively, eaFnCas12a and its engineered variants can be used for genome-editing applications that requires high activity.

Background：Previous studies have shown that in young women, single blastocyst transfer can achieve satisfactory pregnancy results, but there are few studies on the difference between fresh and frozen-thawed single blastocyst transfer. In this retrospective analysis, the purpose of this study was to compare the pregnancy outcomes of young patients who received fresh or frozen-thawed single blastocyst transfer, so as to provide further clinical strategies for single blastocyst transfer.Methods: A retrospective analysis of patients aged ≤35 years old undergoing single blastocyst transfer was performed from January 2018 to December 2018 in the reproductive center of the Second Affiliated Hospital of Wenzhou Medical University. A total of 901 patients were involved and were divided into two groups according to the type of transfer cycle, 693 of which were in the fresh embryo transfer cycle (group A) and 208 of which were in the frozen-thawed embryo transfer cycle (group B). The laboratory and pregnancy outcomes were compared between the groups. Results：The number of oocytes retrieved in group B was significantly more than in group A ( P＜0.05). The early miscarriage rate in group B was higher than in group A, with significant difference(P＜0.05). There were no significant differences in other basic conditions and obstetric pregnancy outcomes between the two groups.Conclusions：Favorable pregnancy outcomes could be obtained in both fresh and frozen-thawed single blastocyst transfer in young patients without increasing the birth defect rate. For patients with risk factors of OHSS such as more oocyte retrieval, ovarian hyper-response, or risk factors of ectopic pregnancy such tubal infertility and the history of ectopic pregnancy, frozen-thawed single blastocyst transfer could be highly recommended in clinical practice. However, since the early miscarriage rate is higher in frozen-thawed embryo transfer group, further research is needed to figure out the cause and possible solutions.

BACKGROUND This study investigated the effectiveness and feasibility of day 4 (D4) morula embryo transfer (ET) in comparison with day 5 (D5) blastocyst ET, with regards to their clinical data, laboratory test results, and pregnancy outcomes. MATERIAL AND METHODS This retrospective cohort study enrolled 1070 patients, including 178 cases in group D4 and 892 cases in group D5. The endpoint was live birth rate after fresh embryo transfer. Furthermore, the clinical outcomes of D4 embryos with different morphology were compared and assigned to 3 groups: in group 1 (n=66) the embryos were compacted but not expanded, in group 2 (n=102) the embryos were compacted and expanded (early blastocyst), and in group 3 (n=10) the embryos were not compacted. RESULTS Groups D4 and D5 had comparable clinical pregnancy rates (53.37% vs. 59.97%) and live birth rates (43.25% vs 50.89%), and there were no significant differences between the 2 groups. In group 3, there was only 1 clinical pregnancy and no live birth. In comparison between group 1 and group 2, the clinical pregnancy rate of group 2 showed an upward trend (48.48% vs 60.78%), but there was no significant difference. There was also no statistically significant difference in the live birth rate between the 2 groups (42.42% vs 49.01%). CONCLUSIONS Transferring of compacted embryos or early blastocysts can result in high clinical pregnancy rates and live birth rates. In addition to the cleavage and blastocyst ET, morula ET may serve as an alternative option for the clinician.

ObjectiveTo explore whether an ultrasound-guided pudendal nerve block (PNB) could decrease anaesthetic use, thereby shortening the length of the second stage of labour in women undergoing epidural analgesia.DesignProspective, single-centre, randomised, double-blind, controlled trial.SettingAn obstetric centre in a general hospital in China.Participants72 nulliparous women were randomised, and 71 women completed the study.InterventionAn ultrasound-guided bilateral PNB was administered to all study participants; the PNB group were given 0.25% ropivacaine 10 mL, while the control group were given 10 mL saline.Main outcome measureThe primary outcome measure was the duration of the second stage of labour. Secondary outcomes included additional bolus administration, total hourly bupivacaine consumption, difference in thickness between the contracted and relaxed rectus abdominis muscle before (DRAM1) and 30 min after (DRAM2) PNB, urge to defecate, maternal cooperation, preservation of the lower limb motor function, tightness of the perineum, and Numeric Rating Scale (NRS) score for pain.ResultsThe duration of the second stage of labour was shorter in the PNB group than in the control group (difference of 33.8 min (95% CI 15.6 to 52.0), pConclusionsNulliparous women with epidural analgesia who received an ultrasound-guided bilateral PNB may reduce their need for bupivacaine and consequently shorten the length of the second stage of labour, therein indicating that a bilateral PNB may serve as an additional effective adjunct method of labour analgesia.Trial registration numberChiCTR-IOR-16009121.

CRISPR-Staphylococcus aureus Cas9 (CRISPR-SaCas9) has been harnessed as an effective in vivo genome-editing tool to manipulate genomes. However, off-target effects remain a major bottleneck that precludes safe and reliable applications in genome editing. Here, we characterize the off-target effects of wild-type (WT) SaCas9 at single-nucleotide (single-nt) resolution and describe a directional screening system to identify novel SaCas9 variants with desired properties in human cells. Using this system, we identified enhanced-fidelity SaCas9 (efSaCas9) (variant Mut268 harboring the single mutation of N260D), which could effectively distinguish and reject single base-pair mismatches. We demonstrate dramatically reduced off-target effects (approximately 2- to 93-fold improvements) of Mut268 compared to WT using targeted deep-sequencing analyses. To understand the structural origin of the fidelity enhancement, we find that N260, located in the REC3 domain, orchestrates an extensive network of contacts between REC3 and the guide RNA-DNA heteroduplex. efSaCas9 can be broadly used in genome-editing applications that require high fidelity. Furthermore, this study provides a general strategy to rapidly evolve other desired CRISPR-Cas9 traits besides enhanced fidelity, to expand the utility of the CRISPR toolkit., CRISPR-SaCas9 technology offers promising solutions to treat genetic disorders by correcting pathogenic mutations, but off-target effects remain a major issue. This study characterizes the off-target activity of wild-type SaCas9 and uses a human cell-based screening system to identify high-fidelity SaCas9 variants, showing that they can dramatically reduce off-target effects.

Objective. To investigate the feasibility and clinical outcome of the all-blastocyst-culture and single blastocyst transfer strategy in women aged ≥35 years. Methods. A retrospective analysis of patients aged ≥35 years undergoing IVF/ICSI was performed from January 2017 to April 2019 in the reproductive center of the Second Affiliated Hospital of Wenzhou Medical University. A total of 155 cases treated with ovarian hyperstimulation by prolonged protocol and implemented single (84 cases) or double (71 cases) blastocyst transfer were collected. Then, patients were further divided into Results. The double-blastocyst-transfer (DBT) group showed higher clinical pregnancy rate and multiple pregnancy rate and lower neonatal birth weight than those in the single-blastocyst-transfer (SBT) group (P<0.05). However, there were no statistically significant differences between the groups in the embryo implantation rate, biochemical pregnancy rate, miscarriage rate, preterm delivery rate, and term birth rate. For patients<38 yr., SBT significantly reduced the multiple pregnancy rate and increased the neonate birth weight without significant reduction in the clinical pregnancy rate. While in the ≥38 yr. group, there are no differences in pregnancy outcomes between SBT and DBT. Logistic regression analysis showed that the number of MII oocytes was positively correlated with the live birth rate (OR=1.18) and negatively correlated with the miscarriage rate (OR=0.844), suggesting that elderly patients with relatively normal ovarian reserve would obtain better prospect in pregnancy. The number of fetal heart beat in pregnancy was negatively correlated with the live birth rate (OR=0.322) and positively correlated with the preterm birth rate (OR=7.16). Conclusion. The strategy of all-blastocyst-culture and single blastocyst transfer is feasible, safe, and effective for elderly patients with normal ovarian reserve, which would reduce the multiple pregnancy rate.

Assisted Oocyte Activation (AOA) with Calcium Ionophore, is possible to manually activate the oocytes and cure globozoospermia, thus leading to successful pregnancy in 1 h after ICSI. But in this case, we report a case that 44 h after ICSI, the arrest zygotes assisted oocyte activation with calcium ionophore, obtained clinical pregnancy and live birth. Accordingly, AOA may provide us with an immediate treatment for embryonic arrest in the future.

Perfluorododecanoic acid (PFDoA) has been used as a surfactant and may have reproductive toxicity. However, whether PFDoA influences Leydig cell development during prepuberty remains unknown. In the present study, 21-day-old male Sprague-Dawley rats were gavaged 0, 5, or 10 mg/kg PFDoA from postnatal day 21 to 35. PFDoA decreased the serum concentrations of testosterone, luteinizing hormone, and follicle-stimulating hormone at doses of 5 and 10 mg/kg without influencing Leydig cell number and proliferation. However, PFDoA down-regulated the expression of Leydig cell genes ( Lhcgr, Scarb1, Star, Cyp11a1, Cyp17a1, and Hsd11b1) or their proteins. PFDoA dose-dependently reduced SIRT1 and PGC-1α levels. PFDoA did not affect AMPK and AKT2 levels but decreased their phosphorylation. We also treated primary progenitor Leydig cells purified from prepubertal rat testes with PFDoA for 24 h. It in vitro lowered viability and decreased mitochondrial membrane potential of progenitor Leydig cells, but it stimulated the generation of the intracellular reactive oxygen species and induced Leydig cell apoptosis at 10 μM. In conclusion, PFDoA blocks rat Leydig cell development during the prepubertal period possibly via targeting AMPK/SIRT1/PGC-1α and AKT2 signaling pathways.

FnCpf1-mediated genome-editing technologies have enabled a broad range of research and medical applications. Recently, we reported that FnCpf1 possesses activity in human cells and recognizes a more compatible PAM (protospacer adjacent motif, 5'-KYTV-3'), compared with the other two commonly used Cpf1 enzymes (AsCpf1 and LbCpf1), which requires a 5'-TTTN-3' PAM. However, due to the efficiency and fidelity, FnCpf1-based clinical and basic applications remain a challenge. The direct repeat (DR) sequence is one of the key elements for FnCpf1-mediated genome editing. In principle, its engineering should influence the corresponding genome-editing activity and fidelity. Here we showed that the DR mutants [G(-9)A and U(-7)A] could modulate FnCpf1 performance in human cells, enabling enhancement of both genome-editing efficiency and fidelity. These newly identified features will facilitate the design and optimization of CRISPR-Cpf1-based genome-editing strategies.

Background Women with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF) are given letrozole before a trigger injection of human chorionic gonadotropin (hCG) to lower estrogen (E2) levels, but can experience ovarian hyperstimulation syndrome (OHSS). The aim of this study was to evaluate the effect of oral letrozole, prior to administration of hCG, on the outcome of IVF and development of OHSS. Material/Methods Retrospective clinical review included 181 cases of women with PCOS who underwent IVF cycles with intracytoplasmic sperm injection (ICSI) and embryo transfer (ET) (IVF/ICSI-ET). The day before the use of hCG, cases were divided into a letrozole-treated group (N=78) and a non-letrozole group (N=103). An oral dose of 2.5 mg qd of letrozole was given when the peak level of E2 was ≥4000 pg/ml during ovarian stimulation and ceased before the day of egg retrieval. Results The letrozole-treated group had a significant increase in the number of retrieved oocytes, viable embryos, and fresh ET rate (P>0.05); peak levels of E2, and E2 levels on the day of the egg retrieval, were significantly higher, and the fertilization rate was significantly lower (P0.05). The incidence OHSS was lower in the letrozole-treated group, but this difference did not reach statistical significance (P>0.05). Conclusions Women with PCOS who underwent IVF, oral treatment with letrozole a day prior to treatment with hCG lowered E2 levels, but did not significantly reduce the incidence of OHSS.

Cpf1 nucleases were recently reported to be highly specific and programmable nucleases with efficiencies comparable to those of SpCas9. AsCpf1 and LbCpf1 require a single crRNA and recognize a 5′-TTTN-3′ protospacer adjacent motif (PAM) at the 5′ end of the protospacer for genome editing. For widespread application in precision site-specific human genome editing, the range of sequences that AsCpf1 and LbCpf1 can recognize is limited due to the size of this PAM. To address this limitation, we sought to identify a novel Cpf1 nuclease with simpler PAM requirements. Specifically, here we sought to test and engineer FnCpf1, one reported Cpf1 nuclease (FnCpf1) only requires 5′-TTN-3′ as a PAM but does not exhibit detectable levels of nuclease-induced indels at certain locus in human cells. Surprisingly, we found that FnCpf1 possesses DNA cleavage activity in human cells at multiple loci. We also comprehensively and quantitatively examined various FnCpf1 parameters in human cells, including spacer sequence, direct repeat sequence and the PAM sequence. Our study identifies FnCpf1 as a new member of the Cpf1 family for human genome editing with distinctive characteristics, which shows promise as a genome editing tool with the potential for both research and therapeutic applications.

Infantile spasm (IS) is an early-onset epileptic encephalopathy that usually presents with hypsarrhythmia on an electroencephalogram with developmental impairment or regression. In this study, whole-exome sequencing was performed to detect potential pathogenic de novo mutations, and finally we identified a novel damaging de novo mutation in SEMA5A and a compound heterozygous mutation in CLTCL1 in three sporadic trios with IS. The expression profiling of SEMA5A in the human brain showed that it was mainly highly expressed in the cerebral cortex, during the early brain development stage (8 to 9 post-conception weeks and 0 to 5 months after birth). In addition, we identified a close protein-protein interaction network between SEMA5A and candidate genes associated with epilepsy, autism spectrum disorder (ASD) or intellectual disability. Gene enrichment and function analysis demonstrated that genes interacting with SEMA5A were significantly enriched in several brain regions across early fetal development, including the cortex, cerebellum, striatum and thalamus (q < 0.05), and were involved in axonal, neuronal and synapse-associated processes. Furthermore, SEMA5A and its interacting genes were associated with ASD, epilepsy syndrome and developmental disorders of mental health. Our results provide insightful information indicating that SEMA5A may contribute to the development of the brain and is associated with IS. However, further genetic studies are still needed to evaluate the role of SEMA5A in IS to definitively establish the role of SEMA5A in this disorder.

This study was designed to to assess perinatal and neonatal outcomes of dizygotic twin pregnancies conceived naturally or by in vitro fertilization (IVF). After strict selection, the study included 470 dizygotic twin pregnancies. There were 249 resulting from IVF treatments and 221 conceiving spontaneously. After adjusting maternal age and primiparity, the results showed that there were no significant differences between the two groups (P > 0.05) in terms of maternal antenatal complications and neonatal outcomes. In conclusion, our study does not reveal increased risks for pregnancy-related complications and adverse neonatal outcomes in dizygotic twin pregnancies following IVF treatments. With these fundamental data, this study could provide a reference for perinatal care and clinical assisted reproductive technology (ART) treatment and help to inform infertile parents about the potential risks of IVF treatments.

To investigate the effects of ovarian puncture for in vitro maturation (IVM) on subsequent in vitro fertilization (IVF) embryo transfer cycles in patients with polycystic ovary syndrome (PCOS).A retrospective study included data from patients admitted to the First Affiliated Hospital of Wenzhou Medical University, China, between January 1, 2008 and December 31, 2014. Patients with PCOS undergoing IVF cycles after having been treated with IVM unsuccessfully were included as the study group and an IVF-procedure data-matched control group of patients undergoing their first IVF cycles was included in a 1:4 ratio. Patients with reproductive anomalies were excluded. Endocrine-hormone levels and antral follicle counts were measured and fertilization-related outcomes were evaluated.There were 49 patients included in the study group and 196 included in the control group. Within the study group, basal luteal-hormone, testosterone, and antral follicle count levels were significantly lower following IVM treatment. The total gonadotropin dose was lower (P0.001) and the duration of stimulation was shorter (P0.001) in the study group compared with the control group. The clinical-pregnancy rate was higher in the study group (P=0.018) and no difference was observed between the groups in ovarian hyper-stimulation syndrome (P=0.633).Previous IVM resulted in improved endocrine profiles and increased clinical-pregnancy rates among patients with PCOS undergoing IVF cycles.

Dimethoate is an organophosphate pesticide. It is widely used in agriculture. However, whether it blocks pubertal development of Leydig cells remains unknown. In the current study, we exposed male Sprague Dawley rats with 7.5 and 15 mg kg−1 dimethoate from postnatal day 35–56. We also exposed Leydig cells isolated from 35-day-old rats for 3 h. Dimethoate reduced serum testosterone levels at 7.5 and 15 mg kg-1 but increased serum luteinizing hormone and follicle stimulating hormone levels at 15 mg kg-1. Dimethoate did not influence Leydig cell number but reduced Leydig cell size and down-regulated Star, Cyp11a1, and Hsd3b1 in Leydig cells as well as their protein expression. Dimethoate inhibited basal androgen output in a dose-dependent manner with the inhibition starting at 0.05 μM. It significantly inhibited luteinizing hormone and 8Br-cAMP stimulated androgen outputs at 50 μM. It significantly inhibited 22R-hydroxycholesterol and progesterone-mediated androgen outputs at 50 μM. Further study demonstrated that dimethoate also down-regulated the expression of Star, Cyp11a1, and Hsd3b1 at 5 or 50 μM in vitro. Dimethoate did not directly inhibit rat testicular steroidogenic enzyme activities at 50 μM. In conclusion, dimethoate targets Star, Cyp11a1, and Hsd3b1 transcription, thus blocking Leydig cell differentiation during puberty.

Ziram is a dimethyldithiocarbamate fungicide, which may influence the male reproductive system as a potential endocrine disruptor. We interrogated the disruption of ziram on rat progenitor Leydig cell development. Prepubertal male Sprague-Dawley rats were orally treated with 0, 2, 4, or 8 mg/kg ziram for 2 weeks. We investigated the effects of ziram on serum testosterone levels, Leydig cell number, and Leydig and Sertoli cell gene and protein expression, SIRT1/PGC-1α levels, and phosphorylation of AKT1, ERK1/2, and AMPK in vivo. We also interrogated the effects of ziram on reactive oxidative species (ROS) level, apoptosis rate, and mitochondrial membrane potential of progenitor Leydig cells in vitro. Ziram decreased serum testosterone and follicle-stimulating hormone levels, the down-regulated Leydig cell-specific gene ( Lhcgr, Scarb1, Star, Cyp17a1, and Hsd17b3), and their protein expression. However, ziram stimulated anti-Müllerian hormone production. Ziram lowered SIRT1/PGC-1α and phosphorylated protein levels of AKT1. Ziram induced ROS and apoptosis and lowered the mitochondrial membrane potential of progenitor Leydig cells in vitro. In conclusion, ziram disrupts Leydig cell development during the prepubertal period potentially through the SIRT1/PGC-1α and phosphorylated AKT1 signaling.

Various types of medical devices used in assisted reproductive technologies (ART) should be detected for their safety by strict biological assays. Mouse embryo assay(MEA)has been recognized as one of the most important and standardized methods with the threshold more than 80% of blastocyst formation rate (BR) after 96 h culture of fertilized eggs. The disadvantage using BR for embryonic quality control has been concerned as it is ubiquitously dependent of embryonic morphology and the detailed data including molecular and genetic information is obviously missing and incomplete. This leads to the urgent requirement for more sensitive and efficient assessments for the quality control of ART. This study evaluated the reliability of an immunofluorescent MEA by counting total cell and differential number of the cells in the inner cell mass (ICM) and trophectoderm (TE) in the blastocyst. This method improved the traditional MEA, provided a sensitive and powerful platform to assess embryonic developmental viability and should be suggested as a standard assay to be globally used for the quality control of medical devices and pre-clinical procedures in ART.

Background The efficiency of prolonged down-regulation caused by a full-dose of gonadotropin-releasing hormone agonist (GnRH-a) injected during different menstrual phases has not yet been researched. Our goal was to evaluate the effects of GnRH-a, which was used in different phases of the menstrual cycle in patients undergoing in vitro fertilization and embryo transfer. Methods This was a retrospective cohort study. A total of 320 patients received a prolonged pituitary down-regulated full-dose (3.75 mg) of triptorelin in the early follicular phase, and 160 patients received the same full-dose of triptorelin during the mid-luteal phase. Clinical and laboratory outcomes were compared between the two groups. Results The basic characteristics of the two groups were comparable. The mean number of retrieved oocytes, fertilized oocytes, cleavage oocytes and good quality embryos were comparable between the two groups. Although there was a higher antral follicle count, cyst formation rate, fertilization rate and cleavage rate in the follicular phase group, no statistically significant effects were seen on implantation rate (41.15% vs. 45.91%), clinical pregnancy rate (60.38% vs. 61.36%), ongoing pregnancy rate (57.74% vs. 57.58%), live birth rate (56.23% vs. 57.58%) or early abortion rate (2.64% vs. 3.79%) per fresh transfer cycle. Moreover, severe ovarian hyperstimulation syndrome rates at the early stage (1.89% vs. 2.27%) were low in both groups. Conclusions Prolonged pituitary down-regulation achieved by utilizing a full-dose of GnRH-a administrated in either phase of the menstrual cycle can have a positive effect on ongoing pregnancy rate and live-birth rate per fresh embryo transfer cycle. Ovarian cyst formation rate was higher in the follicular phase group, but this did not have any adverse impact on clinical results.

Cpf1 has been harnessed as a tool for genome manipulation in various species because of its simplicity and high efficiency. Our recent study demonstrated that FnCpf1 could be utilized for human genome editing with notable advantages for target sequence selection due to the flexibility of the protospacer adjacent motif (PAM) sequence. Multiplex genome editing provides a powerful tool for targeting members of multigene families, dissecting gene networks, modeling multigenic disorders in vivo, and applying gene therapy. However, there are no reports at present that show FnCpf1-mediated multiplex genome editing via a single customized CRISPR RNA (crRNA) array. In the present study, we utilize a single customized crRNA array to simultaneously target multiple genes in human cells. In addition, we also demonstrate that a single customized crRNA array to target multiple sites in one gene could be achieved. Collectively, FnCpf1, a powerful genome-editing tool for multiple genomic targets, can be harnessed for effective manipulation of the human genome.

X-linked juvenile retinoschisis (XLRS) is a retinal disease caused by mutations in the gene encoding retinoschisin (RS1), which leads to a significant proportion of visual impairment and blindness. To develop personalized genome editing based gene therapy, knock-in animal disease models that have the exact mutation identified in the patients is extremely crucial, and that the way which genome editing in knock-in animals could be easily transferred to the patients. Here we recruited a family diagnosed with XLRS and identified the causative mutation (RS1, p.Y65X), then a knock-in mouse model harboring this disease-causative mutation was generated via TALEN (transcription activator-like effector nucleases). We found that the b-wave amplitude of the ERG of the RS1-KI mice was significantly decreased. Moreover, we observed that the structure of retina in RS1-KI mice has become disordered, including the disarray of inner nuclear layer and outer nuclear layer, chaos of outer plexiform layer, decreased inner segments of photoreceptor and the loss of outer segments. The novel knock-in mice (RS1-KI) harboring patient-specific mutation will be valuable for development of treatment via genome editing mediated gene correction.