Embryo selection through non-invasive preimplantation genetic testing with cell-free DNA in spent culture media: a protocol for a multicentre, double-blind, randomised controlled trial.

INTRODUCTION: Morphological 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 ANALYSIS: Overall, 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 DISSEMINATION: The 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 NUMBER: NCT04339166.

Superior Fast-Charging Lithium-Ion Batteries Enabled by the High-Speed Solid-State Lithium Transport of an Intermetallic Cu6 Sn5 Network.

Superior fast charging is a desirable capability of lithium-ion batteries, which can make electric vehicles a strong competition to traditional fuel vehicles. However, the slow transport of solvated lithium ions in liquid electrolytes is a limiting factor. Here, a Lix Cu6 Sn5 intermetallic network is reported to address this issue. Based on electrochemical analysis and X-ray photoelectron spectroscopy mapping, it is demonstrated that the reported intermetallic network can form a high-speed solid-state lithium transport matrix throughout the electrode, which largely reduces the lithium-ion-concentration polarization effect in the graphite anode. Employing this design, superior fast-charging graphite/lithium cobalt oxide full cells are fabricated and tested under strict electrode conditions. At the charging rate of 6 C, the fabricated full cells show a capacity of 145 mAh g-1 with an extraordinary capacity retention of 96.6%. In addition, the full cell also exhibits good electrochemical stability at a high charging rate of 2 C over 100 cycles (96.0% of capacity retention) in comparison to traditional graphite-anode-based cells (86.1% of capacity retention). This work presents a new strategy for fast-charging lithium-ion batteries on the basis of high-speed solid-state lithium transport in intermetallic alloy hosts.

Extremely fast-charging lithium ion battery enabled by dual-gradient structure design.

Extremely fast-charging lithium-ion batteries are highly desirable to shorten the recharging time for electric vehicles, but it is hampered by the poor rate capability of graphite anodes. Here, we present a previously unreported particle size and electrode porosity dual-gradient structure design in the graphite anode for achieving extremely fast-charging lithium ion battery under strict electrode conditions. We develop a polymer binder-free slurry route to construct this previously unreported type particle size-porosity dual-gradient structure in the practical graphite anode showing the extremely fast-charging capability with 60% of recharge in 10 min. On the basis of dual-gradient graphite anode, we demonstrate extremely fast-charging lithium ion battery realizing 60% recharge in 6 min and high volumetric energy density of 701 Wh liter-1 at the high charging rate of 6 C.

Association between prenatal air pollution exposure and risk of hypospadias in offspring: a systematic review and meta-analysis of observational studies.

BACKGROUND: The findings of associations between prenatal air pollution exposure and hypospadias risk in offspring are inconsistent. No systematic review or meta-analysis has yet summarized the present knowledge on the aforementioned topic. METHODS: Relevant manuscripts were identified by searching PubMed and Web of Science databases through January 31, 2020. Summary odds ratios (ORs) with 95% confidence intervals (CIs) in meta-analyses were estimated based on a random effects model. Publication bias was evaluated by funnel plots, Begg's test, and Egger's test. RESULTS: The search identified 3,032 relevant studies. Sixteen studies cumulatively involving 21,701 hypospadias cases and 1,465,364 participants were included. All of these studies were classified as having a low risk of bias. We classified pollutants as nitrogen oxides, particulate matter (PM), ozone, and other exposures. The exposure window to pollutants varied from three months before conception to seven days after delivery. In the meta-analyses, only PM2.5 exposure in the first trimester was related to increased risk of hypospadias (per 10 µg/m3 OR = 1.34; 95% CI: 1.06-1.68). CONCLUSION: We found evidence for an effect of PM2.5 exposure on hypospadias risk. Improvements in the areas of study design, exposure assessment, and specific exposure window are needed to advance this field.

A Nacre-Inspired Separator Coating for Impact-Tolerant Lithium Batteries.

The commercial ceramic nanoparticle coated microporous polyolefin separators used in lithium batteries are still vulnerable under external impact, which may cause short circuits and consequently severe safety threats, because the protective ceramic nanoparticle coating layers on the separators are intrinsically brittle. Here, a nacre-inspired coating on the separator to improve the impact tolerance of lithium batteries is reported. Instead of a random structured ceramic nanoparticle layer, ion-conductive porous multilayers consisting of highly oriented aragonite platelets are coated on the separator. The nacre-inspired coating can sustain external impact by turning the violent localized stress into lower and more uniform stress due to the platelet sliding. A lithium-metal pouch cell using the aragonite platelet coated separator exhibits good cycling stability under external shock, which is in sharp contrast to the fast short circuit of a lithium-metal pouch cell using a commercial ceramic nanoparticle coated separator.

Nanoscale depth control of implanted shallow silicon vacancies in silicon carbide.

Color centers in silicon carbide have recently attracted broad interest as high bright single photon sources and defect spins with long coherence time at room temperature. There have been several methods to generate silicon vacancy defects with excellent spin properties in silicon carbide, such as electron irradiation and ion implantation. However, little is known about the depth distribution and nanoscale depth control of the shallow defects. Here, a method is presented to precisely control the depths of the ion implantation induced shallow silicon vacancy defects in silicon carbide by using reactive ion etching with little surface damage. After optimizing the major etching parameters, a slow and stable etching rate of about 5.5 ± 0.5 nm min-1 can be obtained. By successive nanoscale plasma etching, the shallow defects are brought close to the surface step by step. The photoluminescence spectrum and optically detected magnetic resonance spectra are measured, which confirm that there were no plasma-induced optical and spin property changes of the defects. By tracing the mean counts of the remaining defects after each etching process, the depth distribution of the defects can be obtained for various implantation conditions. Moreover, the spin coherence time T2* of the generated VSi defects is detected at different etch depths, which greatly decreases when the depth is less than 25 nm. The method of nanoscale depth control of silicon vacancies would pave the way for investigating the surface spin properties and the applications in nanoscale sensing and quantum photonics.

Diatomite derived hierarchical hybrid anode for high performance all-solid-state lithium metal batteries.

Lithium metal based anode with hierarchical structure to enable high rate capability, volume change accommodation, and dendritic suppression is highly desirable for all-solid-state lithium metal battery. However, the fabrication of hierarchical lithium metal based anode is challenging due to the volatility of lithium. Here, we report that natural diatomite can act as an excellent template for constructing hierarchical silicon-lithium based hybrid anode for high performance all-solid-state lithium metal battery. This hybrid anode exhibits stable lithium stripping/plating performance over 1000 h with average overpotential lower than 100 mV without any short circuit. Moreover, all-solid-state full cell using this lithium metal composite anode to couple with lithium iron phosphate cathode shows excellent cycling stability (0.04% capacity decay rate for 500 cycles at 0.5C) and high rate capability (65 mAh g-1 at 5C). The present natural diatomite derived hybrid anode could further promote the fabrication of high performance all-solid-state lithium batteries from sustainable natural resources.

Kruppel-like factor 6 regulates Sertoli cell blood-testis barrier.

Blood-testis barrier (BTB) that is constructed by testicular Sertoli cells (SCs) is essential for spermatogenesis. Krüppel-like factor 6 (Klf6), a nuclear transcription regulator, is reported to be associated with tight junction molecules of BTB between SCs during spermatogenesis; however, the specific regulatory role and mechanism of Klf6 in BTB regulation are still unknown. Here, we primarily confirmed the temporal and spatial expression patterns of Klf6 in mouse testes. Then, Klf6 was silenced in mouse cultured SCs using either Klf6-siRNA or Klf6-shRNA lentivirus. We mainly found that: (i) Klf6 was indispensable for the proliferative activity of mouse SCs; (ii) Klf6 regulated the integrity and permeability of BTB; (iii) Klf6 knockdown led to the significant upregulation of Zo-1, Claudin-11 and Vimentin, and downregulation of Claudin-3. Furthermore, Zo-1 and Claudin-3, participated in the tight junction remolding, were determined as targets of transcription factor Klf6 by luciferase assay. In summary, our findings suggest that Klf6 regulates the BTB assembly and disassembly via mainly targeting Zo-1 and Claudin-3 in mouse SCs.

Effects of sperm proteins on fertilization in the female reproductive tract.

Mammalian fertilization that culminates by fusion of the male and female gametes is intricately regulated within the female reproductive tract. To become competent to fertilize an egg, the mammalian spermatozoa that enter the female reproductive tract must undergo a series of physiological changes, including hyperactivation, and capacitation. For reaching full competency, the acrosome, a specialized membrane-bound organelle that covers the anterior part of the sperm head, must undergo an acrosome reaction. For becoming competent to bind an ovum, and to penetrate the zona pellucida and cumulus, many sperm proteins are released in the course of the acrosome reaction. Ultimately, the acrosome binds to the oolemma and fusion of sperm and egg occurs. In this review, we outline current understanding of the roles and effects of some essential sperm proteins and their functions during fertilization in the female reproductive tract.

Regulation of follicular development and differentiation by intra-ovarian factors and endocrine hormones.

Primordial germ cell migration and homing within the gonadal ridge during early embryo development requires oocyte-secreted polypeptide, growth factors, growth and differentiation factors (GDFs), bone morphogenetic proteins, stem cell factor (SCF), and basic fibroblast growth factor (bFGF). During embryogenesis, the germ cells migrate into developing gonads and undergo intra-ovarian development which involves the contact of primordial germ cells with other cells. Further follicular development and differentiation is tightly regulated by hormones and by intraovarian regulators. Maturation of cumulus-oocyte complexes and ovulation are directly controlled by FSH and LH and requires activation of mitogen-activated protein kinase in granulosa cells. The selection of dominant follicles is driven by a series of proliferation and apoptotic events. Together, the available data suggests that follicular development is regulated both by systemic and local factors.

Characterization of the Sperm Proteome and Reproductive Outcomes with in Vitro, Fertilization after a Reduction in Male Ejaculatory Abstinence Period.

Semen samples from men after a short ejaculatory abstinence show improved sperm quality and result in increased pregnancy rates, but the underlying mechanisms remain unclear. Herein, we report that ejaculates from short (1-3 h) compared with long (3-7 days) periods of abstinence showed increases in motile sperm count, sperm vitality, normal sperm morphology, acrosome reaction capacity, total antioxidant capacity, sperm mitochondrial membrane potential, high DNA stainability, and a decrease in the sperm DNA fragmentation index (p, < 0.05). Sperm proteomic analysis showed 322 differentially expressed proteins (minimal fold change of ±1.5 or greater and p, < 0.05), with 224 upregulated and 98 downregulated. These differentially expressed proteins are profoundly involved in specific cellular processes, such as motility and capacitation, oxidative stress, and metabolism. Interestingly, protein trimethyllysine modification was increased, and butyryllysine, propionyllysine, and malonyllysine modifications were decreased in ejaculates from a short versus, long abstinence (p, < 0.05). Finally, the rates of implantation, clinical pregnancy, and live births from in vitro, fertilization treatments were significantly increased in semen samples after a short abstinence. Our study provides preliminary mechanistic insights into improved sperm quality and pregnancy outcomes associated with spermatozoa retrieved after a short ejaculatory abstinence.

Assessment of the development of assisted reproductive technology in Liaoning province of China, from 2012 to 2016.

BACKGROUND: The development of assisted reproduction techniques (ART) has resulted in rapid advances in the treatment of infertility. However, a systematic assessment of ART and its processes and outcomes in China has never been carried out. The goal of this study was to assess the features of ART status from 2012 to 2016 in clinics and in vitro fertilization (IVF) laboratories in Liaoning, the largest IVF province in the northeast of China. METHODS: Data from Jan 1, 2012 to Dec 31, 2016 was retrieved from the assisted reproductive certificate registry of Liaoning province. We extracted data from: i) fresh and thawed cycles; ii) donor sperm and donor egg cycles; iii) intrauterine insemination with husband semen and donor semen (AIH and AID). RESULTS: We showed that: (i) there has been a significant increase in the number of IVF fresh and thawed cycles, and the proportion of cases of primary infertility and secondary infertility has decreased and increased, respectively; (ii) standard long GnRH agonist was the major ovarian stimulation protocol. During the observation period, increasing trends in the use of GnRH antagonists, mild stimulation, and natural cycles were observed; (iii) significant differences in the number of cycles, number of retrieved oocytes, fertilization rates, implantation rates, and sex ratio were noticed between conventional IVF and intracytoplasmic sperm injection; (iv) significant differences in age at treatment for infertility, number of cycles, and ectopic pregnancy rates were noticed between donor sperm cycles and donor egg cycles; (v) significant differences in number of thawed cycles, number of thawed embryos, embryo recovery rates, implantation rates, and clinical pregnancy rates were noticed between day 3 and day 5 embryos; (vi) significant differences in age at treatment for infertility, number of cycles, clinical pregnancy rates, ectopic pregnancy rates, and live birth ratio were noticed between AIH and AID. CONCLUSIONS: ART in Liaoning province has undergone substantial development from 2012 to 2016 in clinics and IVF laboratories. This presentation of detailed ART data will provide researchers, policy makers, and potential ART users a rich source of information about IVF characteristics in the northeast of China.

CRISPR/Cas9-mediated genome editing induces gene knockdown by altering the pre-mRNA splicing in mice.

BACKGROUND: Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated protein 9 (CRISPR/Cas9) has been wildly used to generate gene knockout models through inducing indels causing frame-shift. However, there are few studies concerning the post-transcript effects caused by CRISPR-mediated genome editing. RESULTS: In the present study, we showed that gene knockdown model also could be generated using CRISPR-mediated gene editing by disrupting the boundary of exon and intron in mice (C57BL/6 J). CRISPR induced indel at the boundary of exon and intron (5' splice site) caused alternative splicing and produced multiple different mRNAs, most of these mRNAs introduced premature termination codon causing down expression of the gene. CONCLUSIONS: These results showed that alternative splicing mutants were able to generate through CRISPR-mediated genome editing by deleting the boundary of exon and intron causing disruption of 5' splice site. Although alternative splicing was an unexpected outcome, this finding could be developed as a technology to generate gene knockdown models or to investigate pre-mRNA splicing.

Cyclin B2 can compensate for Cyclin B1 in oocyte meiosis I.

Mammalian oocytes are arrested at the prophase of the first meiotic division for months and even years, depending on species. Meiotic resumption of fully grown oocytes requires activation of M-phase-promoting factor (MPF), which is composed of Cyclin B1 and cyclin-dependent kinase 1 (CDK1). It has long been believed that Cyclin B1 synthesis/accumulation and its interaction with CDK1 is a prerequisite for MPF activation in oocytes. In this study, we revealed that oocyte meiotic resumption occurred in the absence of Cyclin B1. Ccnb1-null oocytes resumed meiosis and extruded the first polar body. Without Cyclin B1, CDK1 could be activated by up-regulated Cyclin B2. Ccnb1 and Ccnb2 double knockout permanently arrested the oocytes at the prophase of the first meiotic division. Oocyte-specific Ccnb1-null female mice were infertile due to failed MPF activity elevation and thus premature interphase-like stage entry in the second meiotic division. These results have revealed a hidden compensatory mechanism between Cyclin B1 and Cyclin B2 in regulating MPF and oocyte meiotic resumption.

Hyperhomocysteinemia in polycystic ovary syndrome: decreased betaine-homocysteine methyltransferase and cystathionine ß-synthase-mediated homocysteine metabolism.

RESEARCH QUESTION: What are the metabolic characteristics of homocysteine in polycystic ovary syndrome (PCOS)? DESIGN: Homocysteine concentrations were determined in serum samples from non-obese and obese control subjects and PCOS patients. Homocysteine metabolism was studied in a rat model of PCOS established using dehydroepiandrosterone (DHEA) or DHEA in combination with a high-fat diet (HFD). RESULTS: It was shown that (i) serum homocysteine concentrations were greater in PCOS patients than in control subjects in the obese group (P < 0.05) and serum homocysteine concentrations were significantly higher in the obese group than in the non-obese group, regardless of PCOS status (both P < 0.05); (ii) serum homocysteine concentrations were significantly increased in DHEA + HFD-induced rats compared with controls (P < 0.05); (iii) when compared with the control group, mRNA concentrations of homocysteine metabolic enzymes Bhmt and Cbs were significantly reduced in the liver tissues of DHEA + HFD-induced rats (both P < 0.0001); (iv) when compared with the control group, there was a significant decrease in the methylation concentrations of the Cbs (P < 0.05) and Bhmt (P < 0.05 and P < 0.0001) promoter in the DHEA + HFD group. The methylation patterns, together with previous data, indicate that hypomethylated promoter-mediated transcriptional activation of Bhmt and Cbs might be a defence mechanism against PCOS-related hyperhomocysteinemia. CONCLUSIONS: These findings indicate that decreased liver Bhmt and Cbs-mediated homocysteine metabolism might have a role in hyperhomocysteinemia in PCOS and provides further evidence for a potential role of decreased liver function in PCOS.

Effects of the visual-feedback-based force platform training with functional electric stimulation on the balance and prevention of falls in older adults: a randomized controlled trial.

BACKGROUND: Force platform training with functional electric stimulation aimed at improving balance may be effective in fall prevention for older adults. Aim of the study is to evaluate the effects of the visual-feedback-based force platform balance training with functional electric stimulation on balance and fall prevention in older adults. METHODS: A single-centre, unblinded, randomized controlled trial was conducted. One hundred and twenty older adults were randomly allocated to two groups: the control group (n = 60, one-leg standing balance exercise, 12 min/d) or the intervention group (n = 60, force platform training with functional electric stimulation, 12 min/d). The training was provided 15 days a month for 3 months by physical therapists. Medial-lateral and anterior-posterior maximal range of sway with eyes open and closed, the Berg Balance Scale, the Barthel Index, the Falls Efficacy scale-International were assessed at baseline and after the 3-month intervention. A fall diary was kept by each participant during the 6-month follow-up. RESULTS: On comparing the two groups, the intervention group showed significantly decreased (p < 0.01) medial-lateral and anterior-posterior maximal range of sway with eyes open and closed. There was significantly higher improvement in the Berg Balance Scale (p < 0.05), the Barthel Index (p < 0.05) and the Falls Efficacy Scale-International (p < 0.05), along with significantly lesser number of injurious fallers (p < 0.05), number of fallers (p < 0.05), and fall rates (p < 0.05) during the 6-month follow-up in the intervention group. CONCLUSION: This study showed that the visual feedback-based force platform training with functional electric stimulation improved balance and prevented falls in older adults.

An alternative strategy treated giant congenital melanocytic nevi with epidermis and superficial dermis of the lesions.

Giant congenital melanocytic nevi (GCMN) are defined as rare pigmented lesions that are believed to form between weeks 9 and 20 of gestation. It is difficult to reconstruct large defects after the removal of the lesions and it has posed a great challenge to the plastic surgeon and dermatologist.Given all those difficulty reconstructing the defects, we try to explore an alternative way to resurfacing the defect after removal of GCMN.Patients with GCMN received single-stage excision. Following the subcutaneous tissue and deep dermis were discarded, epidermis and superficial dermis were harvested as graft substitutes to reconstruct the defects in situ.All of the grafted tissue survived well and skin color in the surgical area gradually became lighter. During the periodicity of follow-up, neither hypertrophic scars nor recurrence were observed. Furthermore, histopathology examination demonstrated that there are no distinct melanocytes gathered in the postoperation lesions.For those GCMN which is difficult to reconstruct with traditional methods, resection of the lesion followed by reconstruction with epidermis skin and superficial dermis from the lesions in situ may be a feasible and alternative therapy method.

Regulation of blood-testis barrier assembly in vivo by germ cells.

The assembly of the blood-testis barrier (BTB) during postnatal development is crucial to support meiosis. However, the role of germ cells in BTB assembly remains unclear. Herein, KitW/KitWV mice were used as a study model. These mice were infertile, failing to establish a functional BTB to support meiosis due to c-Kit mutation. Transplantation of undifferentiated spermatogonia derived from normal mice into the testis of KitW/KitWV mice triggered functional BTB assembly, displaying cyclic remodeling during the epithelial cycle. Also, transplanted germ cells were capable of inducing Leydig cell testosterone production, which could enhance the expression of integral membrane protein claudin 3 in Sertoli cells. Early spermatocytes were shown to play a vital role in directing BTB assembly by expressing claudin 3, which likely created a transient adhesion structure to mediate BTB and cytoskeleton assembly in adjacent Sertoli cells. In summary, the positive modulation of germ cells on somatic cell function provides useful information regarding somatic-germ cell interactions.-Li, X.-Y., Zhang, Y., Wang, X.-X., Jin, C., Wang, Y.-Q., Sun, T.-C., Li, J., Tang, J.-X., Batool, A., Deng, S.-L., Chen, S.-R., Cheng, C. Y., Liu, Y.-X. Regulation of blood-testis barrier assembly in vivo by germ cells.

Melatonin promotes sheep Leydig cell testosterone secretion in a co-culture with Sertoli cells.

Leydig cells synthesize and secrete testosterone, and are regulated by Sertoli cells. These two cell types may work together to regulate testicular androgen production. Studies have shown that Leydig cell androgen synthesis can be dramatically enhanced by Sertoli cells in the presence of melatonin, which can regulate the secretory function of Leydig and Sertoli cells. However, the molecular mechanism of melatonin-regulated Leydig cell androgen production via Sertoli cells remains unclear. Here, we found that 10-7 M melatonin increased testosterone production in co-cultured Leydig and Sertoli cells isolated from sheep. Melatonin increased the expression of stem cell factor and insulin-like growth factor-1 and decreased estrogen synthesis in Sertoli cells. Melatonin promoted insulin-like growth factor-1 and decreased estrogen content via the membrane melatonin receptor 1. It also enhanced stem cell factor expression via the retinoic acid receptor-related orphan receptor alpha. Addition of PD98059, a MEK inhibitor, to Sertoli cell culture demonstrated that the melatonin upregulation of insulin-like growth factor-1 and downregulation of estrogen may be through the MEK/extracellular signal-regulated kinase pathway. Together, these results suggest that melatonin may function through modulating melatonin receptor 1-regulated insulin-like growth factor-1 expression, as well as melatonin receptor 1-induced suppression of estrogen synthesis to increase androgen production in co-cultured Leydig and Sertoli cells.

Autophagy is activated in the ovarian tissue of polycystic ovary syndrome.

The importance of autophagy in polycystic ovary syndrome (PCOS)-related metabolic disorders is increasingly being recognized, but few studies have investigated the role of autophagy in PCOS. Here, transmission electron microscopy demonstrated that autophagy was enhanced in the ovarian tissue from both humans and rats with PCOS. Consistent with this, ovarian granulosa cells from PCOS rats showed increases in the autophagy marker protein light chain 3B (LC3B), whereas levels of the autophagy substrate SQSTM1/p62 were decreased. In addition, the ratio of LC3-II/LC3-I was markedly elevated in human PCOS ovarian tissue compared with normal ovarian tissue. Real-time PCR arrays indicated that 7 and 34 autophagy-related genes were down- and up-regulated in human PCOS , Signal-Net, and regression analysis suggested that there are a wide range of interactions among these 41 genes, and a potential network based on EGFR, ERBB2, FOXO1, MAPK1, NFKB1, IGF1,TP53 and MAPK9 may be responsible for autophagy activation in PCOS. Systematic functional analysis of 41 differential autophagy-related genes indicated that these genes are highly involved in specific cellular processes such as response to stress and stimulus, and are linked to four significant pathways, including the insulin, ERBB, mTOR signaling pathways and protein processing in the endoplasmic reticulum. This study provides evidence for a potential role of autophagy disorders in PCOS in which autophagy may be an important molecular event in the pathogenesis of PCOS.