Zygote最新文献

Infertility aetiology has been shown to be related to reproductive outcomes in the wide reproductive age range. The aim of this study was to examine young women in vitro fertilization (IVF) cycle outcomes according to age and infertility cause. This retrospective cohort study was comprised of 305 couples with a female partner aged 17-25 years with either male or female infertility that underwent a fresh IVF cycle between 2003 and 2020. Comparison according to age groups 17-22 years (n = 117) and 23-25 years (n = 188) showed similar outcomes, except for higher rates of 3 pronuclei (PN) embryos in the younger group. However, allocation to groups by infertility aetiology - male factor (MF) (n = 241) vs. female factor (FF) (n = 64) demonstrated lower fertilization rate in the FF vs. MF group (58% vs. 63%, p = 0.049) and higher percent of 1PN and 3PN embryos (0.7% vs. 0.2% and 0.7% vs. 0.1%, p < 0.001 for both). Chemical pregnancy and live-birth rate were significantly higher in the MF vs. FF group (48.9% vs. 29.5%, p = 0.02 and 41.9% vs. 11.0%, p = 0.038). The only parameter associated with live birth rate in a logistic regression analysis was male infertility aetiology (OR = 2.17, p = 0.038). Young couples undergoing IVF cycles due to female factor infertility have poorer reproductive outcomes compared to male factor-related infertility and higher rates of 1PN and 3PN embryos.

Histone lysine-specific demethylase 4A (KDM4A) plays a critical role in the embryonic development of mammals such as mouse and goat, however its function in zebrafish (Danio rerio) embryogenesis remains poorly understood, due to the existence of two kdm4a paralogs (kdm4aa and kdm4ab) in zebrafish. The current study revealed that kdm4aa^-/- embryos exhibited dramatically increased mortality during gastrulation. RT-qPCR showed that RNA-binding motif protein 46 (rbm46) was downregulated after kdm4aa knockout. CUT&Tag-qPCR revealed that kdm4aa knockout significantly decreased H3K4me3, while increasing H3K9me3 and H3K36me3 at rbm46 promoter. kdm4aa^-/- embryos displayed elevated reactive oxygen species (ROS) and reduced adenosine triphosphate (ATP). And rbm46 mRNA injection alleviated ROS accumulation and increased ATP level, thereby rescuing the lethal phenotype in kdm4aa^-/- embryos. Our findings demonstrate that kdm4aa knockout disturbs zebrafish embryogenesis by suppressing rbm46 mRNA expression.

The study documents the embryonic and larval development of Clarias dussumieri, a Near-Threatened, cultivable, and highly valued food fish endemic to the Western Ghats. Induced breeding facilitated detailed observation of developmental stages using light microscopy. Unfertilized eggs measured 1.5 ± 0.02 mm in diameter and enlarged to 1.7 ± 0.10 mm after fertilization (∼13% increase). The first cleavage occurred at 00:36 ± 00:02 h, reaching 64 cells by 01:35 ± 00:06 h. Epiboly progressed from 30% at 03:20 ± 00:10 h to 50% at 04:30 ± 00:05 h and 90% at 05:50 ± 00:10 h; neurulation was evident by 07:40 ± 01:10 h and somites by 11:08 ± 01:26 h. The first heartbeat appeared during the pharyngula period (17:25 ± 01:30 h), and hatching occurred at 25:30 ± 01:30 h at 26-27°C. Hatched larvae were 4.2 ± 0.02 mm total length, observed few melanophores by 12 h, conspicuous eye pigmentation by 24 h, and body pigmentation spreading by day 2 (5.90 ± 0.04 mm).The yolk sac was fully absorbed by 72 ± 2.50 h post-hatching, marking the onset of exogenous feeding. By day 4 (pre-flexion), larvae reached 7.1 ± 0.02 mm; initial notochord flexion began around day 7 and post-flexion from day 10, with juvenile-like morphology evident by day 25 (15.27-17.80 mm). The standardized timelines and measurements provide a baseline for hatchery practice and conservation aquaculture of C. dussumieri, supporting protocol refinement for improving survival and growth under controlled conditions.

This study describes the embryonic and larval development of the Atabapo butterfly pleco Dekeyseria picta under captive conditions. A total of 19 wild-caught adults (male-to-female ratio of 9:10) were maintained together in a single 1000-L tank operated with a recirculating aquaculture system (RAS), at approximately 26°C, under a controlled 12:12 h light-dark cycle. A total of 21 natural spawning events produced an average of 66.5 ± 2.43 spherical eggs with a mean diameter of 3.896 ± 0.022 mm, characterized by a yellow yolk and a strongly adhesive chorion. Embryonic development lasted between three and seven days, and hatched larvae were classified into five developmental phases. Early phases exhibited limited differentiation and weak pigmentation, whereas advanced phases showed visible eyes, increased pigmentation, and progressive yolk absorption. Heartbeat activity and tail movements were observed throughout all phases. The hatching rate was below 40%, likely influenced by differences in chorion rupture efficiency among embryos at distinct developmental stages. Two developmental strategies potentially contributing to embryonic plasticity were identified: (i) a diapause-like state in which embryos temporarily arrested development at early phases without yolk utilization while remaining responsive to stimuli, and (ii) delayed hatching, in which embryos remained within the chorion for up to seven days, allowing further larval development in a protected environment. These strategies may represent adaptive responses to rapidly fluctuating hydrological and environmental conditions characteristic of the natural habitat of the species and emphasize the role of aquaculture in advancing reproductive knowledge and conservation.

This study aimed to investigate the relationship between oocyte meiotic and developmental competences and antral follicle diameter on random days of estrous in naturally cycling zebu females (Nellore - a tropical Bos indicus breed). Immature oocytes recovered from early antral follicles (diameter of 0.5 to 2 mm) exhibited a higher percentage of intact transzonal projections, but lower viability, smaller diameter and a higher proportion of chromatin decondensation when compared to those recovered from mid- (diameter > 2 to 6 mm) and late antral follicles (diameter > 6 mm), demonstrating that oocytes recovered from early antral follicles lack meiotic and developmental competence. Immature oocytes recovered from mid- or late antral follicles were homogeneous in terms of morphology and size, in addition to exhibiting a high proportion of a pattern of chromatin configuration compatible with high developmental competence, which may help explain the better oocyte quality and improved performance of zebu donors in IVP programs. At the end of the in vitro maturation culture, the percentage of oocytes that completed meiotic maturation was higher when they were recovered from late antral follicles compared to mid antral follicles, although the rate of embryonic development to the blastocyst stage was similar. Our results demonstrated a relationship between the acquisition of competences during the final stages of oocyte growth and morphofunctional events, including the chromatin structure remodeling, but further research is needed to better characterize the functional differences in ovarian physiology between bovine breeds that may impact the oocyte developmental potential.

The objective of this study was to compare embryonic morphokinetic parameters and clinical outcomes of two controlled ovarian stimulation (COS) protocols in women of advanced maternal age (AMA): Pergoveris (r-hFSH:r-hLH, 2:1 ratio) versus r-hFSH monotherapy (GONAL-f). This retrospective, non-interventional descriptive study was conducted at a private university-affiliated IVF center and included 136 ICSI cycles performed in AMA patients between March 2019 and May 2020. Patients were grouped by COS protocol (GONAL-f, n = 64; Pergoveris, n = 72), and embryo morphokinetics and ICSI outcomes were extracted from the clinic's database; the main outcome was time to complete blastulation (tB, hours). Embryos from the Pergoveris group reached tB earlier than those from the GONAL-f group (mean 109.3 h vs 112.6 h), and all morphokinetic milestones occurred sooner with Pergoveris, alongside lower multinucleation rates at the 2-cell and 4-cell stages. Although blastocyst development was higher in the GONAL-f group, Pergoveris was associated with higher oocyte yield and maturity, higher implantation, clinical and ongoing pregnancy rates, and lower miscarriage and OHSS rates; Pergoveris cycles also required higher gonadotropin doses and longer stimulation. Overall, embryos from the r-hFSH:r-hLH group exhibited faster morphokinetic timings and improved implantation and pregnancy outcomes, and prospective studies are warranted to confirm these observations.

This study aimed to evaluate the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and inactivated virus vaccination on intracytoplasmic sperm injection (ICSI) outcomes in infertile couples. A retrospective case-control study was conducted at the Royan Institute from August 2020 to March 2022. The study included 90 couples in the COVID-19 infection phase and 31 in the vaccination phase. A total of 30 infected but unvaccinated couples were compared to a control group of 60 couples with no COVID-19 infection or vaccination history. Additionally, 31 couples underwent treatment before and after receiving the Sinopharm inactivated vaccine. Key variables analysed included sperm parameters (concentration, motility, progressive motility and morphology), ovarian parameters (antral follicle count, oocyte retrieval), embryological outcomes and pregnancy outcomes. SARS-CoV-2 infection significantly reduced sperm motility (P = 0.02) and progressive motility (P = 0.01) compared to controls. Sperm concentration and morphology showed non-significant declines. Post-vaccination analysis revealed similar but statistically insignificant changes in sperm parameters. Ovarian stimulation parameters and embryological outcomes remained unaffected by both infection and vaccination. Although biochemical, clinical pregnancy and live birth rates were lower among the infected group, these differences did not reach statistical significance (p = 0.16, 0.08 and 0.09). SARS-CoV-2 infection has been associated with impaired sperm progressive motility, which may negatively influence ICSI outcomes. In contrast, vaccination with an inactivated virus does not appear to impact fertility outcomes. These findings provide crucial guidance for physicians and infertile couples managing treatments during and after the pandemic, suggesting the need for extended recovery periods before ART procedures following COVID-19 infection.

Purpose: To compare the effect of two different assisted hatching laser protocols thinning assisted hatching laser (TAH) vs drilling of assisted hatching laser (DAH) and non-assisted hatching control group (NAC) on clinical pregnancy and live birth rates in frozen thawed cleavage stage embryo transfer cycles.

Patients and methods: This study included 310 infertile patients who underwent frozen embryo transfer (FET) cycles from 2021 to 2022 at the ART Unit of the Medical Point Hospital of Izmir University of Economics, Izmir. Patients included in the study were those between 20 and 40 years of age, who had undergone frozen-thawed embryo transfer after 'freeze-all' protocols. The exclusion criteria were azoospermia and degenerated embryos. In TAH, laser thinning was performed by making 4-5 shots at a depth of 50% of the thickness of the zona pellucida (ZP). In DAH, the laser opening was made from the outer part of the ZP to the inner part. In the last group in NAC, assisted hatching was not performed. Clinical pregnancy and ongoing pregnancy rates were compared between the TAH, DAH and NAC cycles.

Results: There was no difference in terms of the age of the woman, the BMI and the sperm parameters in the three groups. There were no statistical differences between the groups in terms of the number of oocytes, embryos and the quality of the transferred embryos. Clinical pregnancy in thinning assisted hatching laser (TAH), drilling of assisted hatching laser (DAH), non-assisted hatching control group (NAC) cycles (38% vs 39% vs 45% p = 0.842, respectively.), ongoing pregnancy (34% vs 32% vs 39%; p = 0.670, respectively.) and live birth rates (34% vs 29% vs 35,4%; p = 0.586, respectively) were similar in three groups.

Conclusion: In conclusion, no significant differences were found between the TAH, DAH and NAC groups in terms of ART outcomes.

Extracellular vesicles (EVs) are implicated in various functions within the complex mechanisms of intercellular communication. There are several subpopulations of EVs, including apoptotic bodies, microvesicles and exosomes. These nanovesicles are capable of transferring functional proteins and genetic information to alter the phenotype and function of recipient cells. In animal reproduction, numerous studies have demonstrated that EVs are actively involved in the regulation of different physiological events, modulating a variety of processes such as follicular development, spermatogenesis, oocyte maturation, fertilization and embryo development, with results indicating improved gamete quality, embryo development and cryotolerance. Additionally, EVs show therapeutic potential in restoring reproductive function and supporting maternal-embryonic communication in both domestic and wild species. Therefore, the present review aimed to describe the main studies conducted using EVs in the field of animal reproduction, highlighting their biological relevance, experimental applications and future prospects for clinical implementation in assisted reproductive technologies.

Intracytoplasmic sperm injection (ICSI) is a widely used assisted reproduction technique, but in cattle it faces major challenges due to inefficient oocyte activation after sperm microinjection. This study investigated different oocyte activation strategies and assessed the potential role of reducing agents glutathione (GSH), cysteamine (Cys) and dithiobutylamine (DTBA) to improve sperm head decondensation and embryo development following Piezo-ICSI. Haploid parthenogenetic activation using different ethanol concentrations (1%, 3%, 7% and 10%) failed to yield blastocysts, while diploid activation with ethanol or ionomycin combined with inhibitors significantly improved cleavage (43-55%) and blastocyst rates (14-27%), respectively. However, applying two ethanol pulses was detrimental, reducing both cleavage and blastocysts likely due to toxic overexposure. Sperm head decondensation compounds in Piezo-ICSI showed a high percentage of inactivated oocytes (75% GSH, 55% Cys and 40% DTBA). The highest male pronuclear formation rates were observed in the control without sperm head decondensation (21%) and with DTBA treatment (10%). Despite this, the treatment with Cys resulted in higher developmental potential to the blastocyst stage (22%) comparable to the control (24%). These data suggest that the inclusion of sperm head decondensing agents could represent a promising new strategy for enhancing the early in vitro development of ICSI-generated embryos. However, for this purpose, careful optimization of the concentration and incubation time of these decondensing compounds is essential.