Kinesin KIF3A regulates meiotic progression and spindle assembly in oocyte meiosis.

Kinesin family member 3A (KIF3A) is a microtubule-oriented motor protein that belongs to the kinesin-2 family for regulating intracellular transport and microtubule movement. In this study, we characterized the critical roles of KIF3A during mouse oocyte meiosis. We found that KIF3A associated with microtubules during meiosis and depletion of KIF3A resulted in oocyte maturation defects. LC-MS data indicated that KIF3A associated with cell cycle regulation, cytoskeleton, mitochondrial function and intracellular transport-related molecules. Depletion of KIF3A activated the spindle assembly checkpoint, leading to metaphase I arrest of the first meiosis. In addition, KIF3A depletion caused aberrant spindle pole organization based on its association with KIFC1 to regulate expression and polar localization of NuMA and γ-tubulin; and KIF3A knockdown also reduced microtubule stability due to the altered microtubule deacetylation by histone deacetylase 6 (HDAC6). Exogenous Kif3a mRNA supplementation rescued the maturation defects caused by KIF3A depletion. Moreover, KIF3A was also essential for the distribution and function of mitochondria, Golgi apparatus and endoplasmic reticulum in oocytes. Conditional knockout of epithelial splicing regulatory protein 1 (ESRP1) disrupted the expression and localization of KIF3A in oocytes. Overall, our results suggest that KIF3A regulates cell cycle progression, spindle assembly and organelle distribution during mouse oocyte meiosis.

[Application of convolutional neural networks for the classification of metaphase chromosomes].

OBJECTIVE: To train a deep convolutional neural networks (CNN) using a labeled data set to classify the metaphase chromosomes and test its accuracy for chromosomal identification. METHODS: Three thousand and three hundred individuals undergoing surveillance for chromosomal disorders at the Laboratory for Comprehensive Prevention and Treatment of Birth Defects, Ningbo Maternal and Child Health Care Hospital from January 2013 to July 2019 were enrolled. A total of 3 300×46 chromosome images were included, of which 70% were used as the training set and 30% were used as the test set for the deep CNN. The accuracy of chromosome counting and "cutting + recognition + arrangement + automatic analysis" of the model were respectively evaluated. Another 80 images were collected to record the time and accuracy of chromosome classification by geneticists and the model, respectively, so as to assess the practical value of the model. RESULTS: The CNN model was used to count the chromosomes with an accuracy of 61.81%, and the "cutting + recognition + arrangement + automatic analysis" accuracy of the model was 96.16%. Compared with manual operation, the classification time of the CNN model has been greatly reduced, and its karyotyping accuracy was only 3.58% lower than that of geneticists. CONCLUSION: The CNN model has a high performance for chromosome classification and can significantly reduce the work load involved with the segmentation and classification and improve the efficiency of chromosomal karyotyping, thereby has a broad application prospect.

Effects of flaxseed oil supplementation on metaphase II oocyte rates in IVF cycles with decreased ovarian reserve: a randomized controlled trial.

Background: This study was designed to explore the effects of flaxseed oil on the metaphase II (MII) oocyte rates in women with decreased ovarian reserve (DOR). Methods: The women with DOR were divided into a study group (n = 108, flaxseed oil treatment) and a control group (n = 110, no treatment). All patients were treated with assisted reproductive technology (ART). Subsequently, the ART stimulation cycle parameters, embryo transfer (ET) results, and clinical reproductive outcomes were recorded. The influencing factors affecting the MII oocyte rate were analyzed using univariate analysis and multivariate analysis. Results: Flaxseed oil reduced the recombinant human follicle-stimulating hormone (r-hFSH) dosage and stimulation time and increased the peak estradiol (E2) concentration in DOR women during ART treatment. The MII oocyte rate, fertilization rate, cleavage rate, high-quality embryo rate, and blastocyst formation rate were increased after flaxseed oil intervention. The embryo implantation rate of the study group was higher than that of the control group (p = 0.05). Additionally, the female age [odds ratio (OR): 0.609, 95% confidence interval (CI): 0.52-0.72, p < 0.01] was the hindering factor of MII oocyte rate, while anti-Müllerian hormone (AMH; OR: 100, 95% CI: 20.31-495, p < 0.01), peak E2 concentration (OR: 1.00, 95% CI: 1.00-1.00, p = 0.01), and the intake of flaxseed oil (OR: 2.51, 95% CI: 1.06-5.93, p = 0.04) were the promoting factors for MII oocyte rate. Conclusion: Flaxseed oil improved ovarian response and the quality of oocytes and embryos, thereby increasing the fertilization rate and high-quality embryo rate in DOR patients. The use of flaxseed oil was positively correlated with MII oocyte rate in women with DOR. Clinical trial number: https://www.chictr.org.cn/, identifier ChiCTR2300073785.

Molecular alterations in metaphase chromosomes induced by bleomycin.

Chromosomes are intranuclear structures, their main function is to store and transmit genetic information during cell division. They are composed of tightly packed DNA in the form of chromatin, which is constantly exposed to various damaging factors. The resulting changes in DNA can have serious consequences (e.g. mutations) if they are not repaired or repaired incorrectly. In this article, we studied chromosomes isolated from human cervical cancer cells (HeLa) exposed to a genotoxic drug causing both single- and double-strand breaks. Specifically, we used bleomycin to induce DNA damage. We followed morphological and chemical changes in chromosomes upon damage induction. Atomic force microscopy was used to visualize the morphology of chromosomes, while Raman microspectroscopy enabled the detection of changes in the chemical structure of chromatin with the resolution close to the diffraction limit. Additionally, we extracted spectra corresponding to chromosome I or chromatin from hyperspectral Raman maps with convolutional neural networks (CNN), which were further analysed with the principal component analysis (PCA) algorithm to reveal molecular markers of DNA damage in chromosomes. The applied multimodal approach revealed simultaneous morphological and molecular changes, including chromosomal aberrations, alterations in DNA conformation, methylation pattern, and increased protein expression upon the bleomycin treatment at the level of the single chromosome.

Whole-Mount Immunofluorescence Staining to Visualize Cell Cycle Progression in Mouse Oocyte Meiosis.

Whole-mount immunofluorescence allows direct visualization of the cellular architecture within cells. Here, we apply this technique to mouse oocytes to visualize spindle morphology and microtubule attachments to kinetochores, using a technique we call "cold treatment," at various phases of the meiotic cell cycle. This method allows the analysis of spindle structures at different meiosis I stages and at metaphase II. An adaptation of the protocol to the cell cycle stage of interest is described.

MAARS Software for Automatic and Quantitative Analysis of Mitotic Progression.

In this chapter, we describe a software called MAARS (Mitotic Analysis And Recording System) that enables automatic and quantitative analysis of mitotic progression on an open-source platform. This computer-assisted analysis of cell division allows the unbiased acquisition of multiple parameters such as cell shape or size, metaphase or anaphase delays, as well as various mitotic abnormalities. This chapter describes the power of such an expert system to highlight the complexity of the mechanisms required to prevent mitotic chromosome segregation errors, leading to aneuploidy.

PAK1-Dependent Regulation of Microtubule Organization and Spindle Migration Is Essential for the Metaphase I-Metaphase II Transition in Porcine Oocytes.

P21-activated kinase 1 (PAK1) is a critical downstream target that mediates the effect of small Rho GTPase on the regulation of cytoskeletal kinetics, cell proliferation, and cell migration. PAK1 has been identified as a crucial regulator of spindle assembly during the first meiotic division; however, its roles during the metaphase I (MI) to metaphase II (MII) transition in oocytes remain unclear. In the present study, the potential function of PAK1 in regulating microtubule organization and spindle positioning during the MI-MII transition was addressed in porcine oocytes. The results showed that activated PAK1 was co-localized with α-tubulin, and its expression was increased from the MI to MII stage (p < 0.001). However, inhibiting PAK1 activity with an inhibitor targeting PAK1 activation-3 (IPA-3) at the MI stage decreased the first polar body (PB1) extrusion rate (p < 0.05), with most oocytes arrested at the anaphase-telophase (ATI) stage. IPA-3-treated oocytes displayed a decrease in actin distribution in the plasma membrane (p < 0.001) and an increase in the rate of defects in MII spindle reassembly with abnormal spindle positioning (p < 0.001). Nevertheless, these adverse effects of IPA-3 on oocytes were reversed when the disulfide bond between PAK1 and IPA-3 was reduced by dithiothreitol (DTT). Co-immunoprecipitation revealed that PAK1 could recruit activated Aurora A and transform acidic coiled-coil 3 (TACC3) to regulate spindle assembly and interact with LIM kinase 1 (LIMK1) to facilitate actin filament-mediated spindle migration. Together, PAK1 is essential for microtubule organization and spindle migration during the MI-MII transition in porcine oocytes, which is associated with the activity of p-Aurora A, p-TACC3 and p-LIMK1.

Spindle shape and volume differ in high- and low-quality metaphase II oocytes.

In brief: Optical coherence microscopy non-invasively visualizes metaphase II spindles allowing for quantitative analysis of their volume and shape, which may prove useful in the assessment of the oocyte quality. Using a mouse model, we showed also that analysis of spindle length combined with morphokinetics improves the evaluation of the resulting embryos. Abstract: The proper development of embryos strongly depends on the quality of oocytes, so the evaluation of oocytes may be a useful initial step in IVF procedures. Additionally, it enables embryologists to make more informed decisions regarding the treatments chosen for the patients and better manage patients' expectations. Optical coherence microscopy (OCM) allows for non-invasive 3D visualization of intracellular structures, such as spindles or nuclei, which have been linked to the success of embryonic development. Here, we applied a mouse model to examine whether OCM imaging could be used in the quality assessment of metaphase II (MII) oocytes. We showed that quantitative parameters describing the shape and volume of the MII spindle were associated with the quality of the resulting embryos, including the likelihood of blastocyst formation and the embryos' ability to differentiate the trophectoderm and primitive endoderm, but not the epiblast. We also created a multivariate linear regression model, combining OCM-based quantification of MII spindles with morphokinetic analysis of the embryos, that allowed for improved evaluation of the embryo quality. Finally, we proved that OCM does not interfere with the viability of the scanned cells, at least during the preimplantation development. Therefore, we believe that OCM-based quantitative assessment of MII spindles can improve the oocyte and embryo selection in IVF procedures.

Usable blastocysts developed from in-vitro-matured metaphase I oocytes in preimplantation genetic testing cycles.

RESEARCH QUESTION: Are blastocysts derived from in-vitro-matured metaphase I (MI) oocytes less likely to produce usable embryos for transfer compared with those derived from in-vivo-matured oocytes in cycles undergoing preimplantation genetic testing (PGT)? DESIGN: The primary outcome was usable blastocyst rate, which was compared between blastocysts derived from in-vitro-matured MI oocytes after ovarian stimulation and from in-vivo-matured oocytes. Logistic regression analysis using generalized estimating equations was used to control for confounders in the analysis of factors that may influence the chance of a blastocyst being usable and in the comparison of embryological outcomes. Student's t-test, Mann-Whitney U test, chi-squared tests or Fisher's exact tests were used to compare clinical and pregnancy outcomes. RESULTS: A total of 1810 injected metaphase II (MII) oocytes from 154 PGT cycles involving 154 couples were included in this study. A total of 1577 MII oocytes were in-vivo-matured and 233 were in-vitro-matured MI oocytes. The usable blastocyst rate was similar between the in-vitro-matured MI oocyte group and the in-vivo-matured oocyte group (adjusted RR 0.97, 95% CI 0.40 to 2.34). Three live births were achieved using usable blastocysts derived from in-vitro-matured MI oocytes. CONCLUSIONS: If in-vitro-matured MI oocytes can be fertilized and develop into blastocysts, their ability to provide usable embryos for transfer is similar compared with those developed from in-vivo-matured oocytes. These blastocysts could be considered valuable for women with few viable embryos in assisted reproductive technology cycles.

Multiple reorganizations of the lateral elements of the synaptonemal complex facilitate homolog segregation in Bombyx mori oocytes.

Although Lepidopteran females build a synaptonemal complex (SC) in pachytene, homologs do not crossover, necessitating an alternative method of homolog conjunction. In Bombyx mori oocytes, the SC breaks down at the end of pachytene, and homolog associations are maintained by a large oocyte-specific structure, which we call the bivalent bridge (BB), connecting paired homologs. The BB is derived from at least some components of the SC lateral elements (LEs). It contains the HORMAD protein HOP1 and the LE protein SYCP2 and is formed by the fusion of the two LE derivatives. As diplotene progresses, the BB increases in width and acquires a layered structure with a thick band of HOP1 separating two layers of SYCP2. The HOP1 interacting protein, PCH2, joins the BB in mid-diplotene, and by late-diplotene, it lies in the middle of the HOP1 filament. This structure is maintained through metaphase I. SYCP2 and PCH2 are lost at anaphase I, and the BB no longer connects the separating homologs. However, a key component of the BB, HOP1, remains at the metaphase I plate. These changes in organization of the BB occur simultaneously with the movement of the kinetochore protein, DSN1, from within the BB at mid-diplotene to the edge of the homologs facing the poles by metaphase I. We view these data in context of models in which SC components and regulators can be repurposed to achieve different functions, a fascinating example of evolution achieving homolog conjunction in an alternative way with recycling of SC proteins.

Effect of vitrification on protein O-GlcNAcylation in mouse metaphase II oocytes.

In brief: Oocyte vitrification leads to DNA hypomethylation, which results in defect in early embryo development. This study reveals that oocyte vitrification impairs the DNA methylation pattern by influencing protein O-GlcNAcylation. Abstract: Oocyte vitrification leads to decreased DNA methylation levels, which impairs the quality and the developmental potential of oocytes. However, the underlying molecular mechanism still need to be further revealed. In this study, mouse metaphase II (M II) oocytes were frozen by vitrification technology, while fresh oocytes were used as the control group. The effect of oocyte vitrification on protein O-GlcNAcylation and its impact on the developmental potential of oocytes were elucidated. We found that the protein O-GlcNAcylation levels were significantly increased in vitrified oocytes. Increase of protein O-GlcNAcylation levels in control oocytes by PUGNAc (an O-GlcNAcase inhibitor) decreases blastocyst rate after parthenogenetic activation (20.82% in PUGNAc-treated group; 53.82% in control group, P < 0.05). We also discovered that DNA methylation was disrupted in two-cell embryos derived from vitrified oocytes, resulting in decreased 5mC and increased 5hmC, showing similar phenotypes to that derived from PUGNAc-treated oocytes. In vitrified and PUGNAc-treated oocytes, O-GlcNAcylated TET3 was significantly increased. Notably, by inhibiting protein O-GlcNAcylation in vitrified oocytes using OSMI1 (an O-GlcNAc transferase inhibitor) we restored the DNA methylation in two-cell embryos and ameliorated the developmental defects in early embryo. Thus, elevated protein O-GlcNAcylation in vitrified oocytes is an essential contributor to their declining embryonic developmental potential. Modulation of protein O-GlcNAcylation improves the developmental potential of vitrified oocytes.

Differential transcript usage across mammalian oocytes at the germinal vesicle and metaphase II stages.

Ongoing progress in mRNA-Sequencing technologies has significantly contributed to the refinement of assisted reproductive technologies. However, the prior investigations have predominantly concentrated on alterations in overall gene expression levels, thereby leaving a considerable gap in our understanding of the influence of transcript isoform expression on fundamental cellular mechanisms of oocytes. Given the efficacy of differential transcript usage (DTU) analysis to address such knowledge, we conducted comprehensive DTU analysis utilizing mRNA-Seq datasets of germinal vesicle (GV) and metaphase II (MII) oocytes across six mammalian species from the SRA database, including cow, donkey, horse, human, mouse, and pig. To further illuminate the roles of these genes, we also conducted a rigorous Gene Ontology (GO) term enrichment analysis. While the DTU analysis of each species exhibited several genes with alterations in their transcript isoform usage, referred to as DTU genes, this study focused on only ten cross-species DTU genes sharing among a minimum of five distinct species (FDR≤0.05). These cross-species DTU genes were as follows: ABCF1, CDC6, CFAP36, CNOT10, DNM3, IWS1, NBN, NDEL1, RAD50 and ZCCHC17. GO term enrichment analysis unveiled the alignment of these cross-species DTU gene functions with RNA and cell-cycle control mechanisms across diverse mammalian species, thereby suggesting their vital roles during oocyte maturation. Further exploration of the transcript isoforms of these genes hence bore the potential to uncover novel transcript isoform markers for future reproductive technologies in both human and animal contexts.

Incorrect recombination partner associations contribute to meiotic instability of neo-allopolyploid Arabidopsis suecica.

Combining two or more related homoeologous genomes in a single nucleus, newly formed allopolyploids must rapidly adapt meiosis to restore balanced chromosome segregation, production of euploid gametes and fertility. The poor fertility of such neo-allopolyploids thus strongly selects for the limitation or avoidance of genetic crossover formation between homoeologous chromosomes. In this study, we have reproduced the interspecific hybridization between Arabidopsis thaliana and Arabidopsis arenosa leading to the allotetraploid Arabidopsis suecica and have characterized the first allopolyploid meioses. First-generation neo-allopolyploid siblings vary considerably in fertility, meiotic behavior and levels of homoeologous recombination. We show that centromere dynamics at early meiosis is altered in synthetic neo-allopolyploids compared with evolved A. suecica, with a significant increase in homoeologous centromere interactions at zygotene. At metaphase I, the presence of multivalents involving homoeologous chromosomes confirms that homoeologous recombination occurs in the first-generation synthetic allopolyploid plants and this is associated with a significant reduction in homologous recombination, compared to evolved A. suecica. Together, these data strongly suggest that the fidelity of recombination partner choice, likely during the DNA invasion step, is strongly impaired during the first meiosis of neo-allopolyploids and requires subsequent adaptation.

Transcriptomic profiles reveal the characteristics of oocytes and cumulus cells at GV, MI, and MII in follicles before ovulation.

BACKGROUND: The oocyte and its surrounding cumulus cells (CCs) exist as an inseparable entity. The maturation of the oocyte relies on communication between the oocyte and the surrounding CCs. However, oocyte evaluation is primarily based on morphological parameters currently, which offer limited insight into the quality and competence of the oocyte. Here, we conducted transcriptomic profiling of oocytes and their CCs from 47 patients undergoing preimplantation genetic testing for aneuploidy (PGT-A). We aimed to investigate the molecular events occurring between oocytes and CCs at different stages of oocyte maturation (germinal vesicle [GV], metaphase I [MI], and metaphase II [MII]). Our goal is to provide new insights into in vitro oocyte maturation (IVM). RESULTS: Our findings indicate that oocyte maturation is a complex and dynamic process and that MI oocytes can be further classified into two distinct subtypes: GV-like-MI oocytes and MII-like-MI oocytes. Human oocytes and cumulus cells at three different stages of maturation were analyzed using RNA-seq, which revealed unique transcriptional machinery, stage-specific genes and pathways, and transcription factor networks that displayed developmental stage-specific expression patterns. We have also identified that both lipid and cholesterol metabolism in cumulus cells is active during the late stage of oocyte maturation. Lipids may serve as a more efficient energy source for oocytes and even embryogenesis. CONCLUSIONS: Overall, our study provides a relatively comprehensive overview of the transcriptional characteristics and potential interactions between human oocytes and cumulus cells at various stages of maturation before ovulation. This study may offer novel perspectives on IVM and provide a reliable reference data set for understanding the transcriptional regulation of follicular maturation.

NUSAP1 regulates mouse oocyte meiotic maturation.

The correct assembly of the spindle apparatus directly regulates the precise separation of chromosomes in mouse oocytes, which is crucial for obtaining high-quality oocytes capable of successful fertilization. The localization, assembly, migration, and disassembly of the spindle are regulated by a series of spindle-associated proteins, which exhibit unique expression level variations and specific localization in oocytes. Proteomic analysis revealed that among many representative spindle-associated proteins, the expression level of nucleolar and spindle-associated protein 1 (NUSAP1) significantly increased after meiotic resumption, with a magnitude of change higher than that of other proteins. However, the role of NUSAP1 during oocyte meiosis maturation has not been reported. Here, we report that NUSAP1 is distributed within the cell nucleus during the germinal vesicle (GV) oocytes with non-surrounded nucleolus stage and is not enriched in the nucleus during the GV-surrounded nucleolus stage. Interestingly, NUSAP1 forms distinct granular aggregates near the spindle poles during the prophase of the first meiotic division (Pro-MI), metaphase I, and anaphase I/telophase I stages. Nusap1 depletion leads to chromosome misalignment, increased aneuploidy, and abnormal spindle assembly, particularly a decrease in spindle pole width. Correspondingly, RNA-seq analysis revealed significant suppression of the "establishment of spindle orientation" signaling pathway. Additionally, the attenuation of F-actin in NUSAP1-deficient oocytes may affect the asymmetric division process. Gene ontology analysis of NUSAP1 interactomes, identified through mass spectrometry here, revealed significant enrichment for RNA binding. As an RNA-binding protein, NUSAP1 is likely involved in the regulation of messenger RNA homeostasis by influencing the dynamics of processing (P)-body components. Overall, our results demonstrate the critical importance of precise regulation of NUSAP1 expression levels and protein localization for maintaining mouse oocyte meiosis.

Alloprevotella Can be Considered as a Potential Oral Biomarker in Intestinal Metaphase of Gastric Patients.

Gastric cancer is a malignant tumor with high incidence and death rate. Every year, Approximately 950,000 new cases of gastric cancer occur globally with nearly 700000 deaths,so gastric precancerous lesions(GPL) was crucial and important.At present, the effective diagnostic methods for gastric precancerous lesions are generally gastroscope and pathological changes of gastric mucosal, but those methods were invasive and would bring some pains to patients and not suitable for frequent and large-scale screening of gastric cancer or GPL.This study aimed to look for a sensitive,effective and non-invasive diagnostic method to improve the early diagnosis rate of GLP, and thereby reduce the incidence and death rate of gastric cancer.Tongue diagnosis is one of the classic diagnostic methods in traditional Chinese medicine(TCM).The tongue was closely related to the spleen and stomach.In the study, we collected 133 patients with chronic gastritis, including 53 cases in inflammatory group, 31 cases in atrophic group, and 49 cases in intestinal metaplasia group. and we analyzed the correlation between tongue,microbiota of tongue coating and clinical symptoms of GLP.The results showed that greasy coating was closely related to the intestinal metaphase of patients, indicating that greasy coating was closed link with intestinal metaphase phase of patients.Abundance of 209 genus were significant differences between greasy and non-greasy coating in intestinal metaphase phase of patients, Top10 were Streptococcus,norank_p__Saccharibacteria,Alloprevotella, Atopobium, Megasphaera, Gemella, Moraxella,unclassified_f__Prevotellaceae, Solobacterium and Stomatobaculum. Alloprevotella and Streptococcus were important genus markers and Alloprevotella was selected as a potential oral biomarker to diagnose intestinal metaphase phase of patients, the AUC value is 0.74.

TUBA1A licenses APC/C-mediated mitotic progression to drive glioblastoma growth by inhibiting PLK3.

Glioblastoma (GBM) is the most common, aggressive, and chemorefractory primary brain tumor in adults. Identifying novel drug targets is crucial for GBM treatment. Here, we demonstrate that tubulin alpha 1a (TUBA1A) is significantly upregulated in GBM compared to low-grade gliomas (LGG) and normal tissues. High TUBA1A expression is associated with poor survival in GBM patients. TUBA1A knockdown results in mitotic arrest and reduces tumor growth in mice. TUBA1A interacts with the polo-like kinase 3 (PLK3) in the cytoplasm to inhibit its activation. This interaction licenses activation of the anaphase-promoting complex or cyclosome (APC/C) to ensure proper Foxm1-mediated metaphase-to-anaphase transition and mitotic exit. Overall, our findings demonstrate that targeting TUBA1A attenuates GBM cell growth by suppressing mitotic progression in a PLK3-dependent manner.

Protective Effect of Docetaxel Against Autophagy-Related Genes in Vitrification of Mouse Metaphase II Oocytes.

Background: Autophagy is a conservative mechanism for cell survival as the main response of cells to stress conditions. The present study aimed to assess the effect of docetaxel on the survival, fertilization, and expression of autophagy-related genes in vitrified oocytes. Methods: The study was conducted in 2018 at the Stem Cells Technology Research Center, Shiraz University of Medical Sciences (Shiraz, Iran). Denuded oocytes were randomly selected and assigned to five groups, namely control (n=133), docetaxel (n=136), docetaxel+cryoprotectants (n=146), docetaxel+vitrification (n=138), and vitrification (n=145). The effect of vitrification on the expression of autophagy-related gene 5 (ATG5) and Beclin-1 was determined using a real-time polymerase chain reaction. Data were analyzed using SPSS software (version 26.0) and GraphPad Prism 9. Results: Survival and fertilization rates in each experimental group were significantly reduced compared to the control group (P=0.001). After in vitro fertilization of oocytes, the 2-cell formation rate was significantly reduced in the docetaxel+vitrification and vitrification groups compared to the control and docetaxel groups (P=0.001 and P=0.001, respectively). Pre-incubation of oocytes with docetaxel reduced gene expression levels of Beclin-1 and ATG5 in the docetaxel+cryoprotectants and docetaxel+vitrification groups (P=0.001 and P=0.019, respectively). The expression level of these genes was also reduced in the docetaxel group compared to the control group (P=0.001). Conclusion: Incubation of mouse metaphase II oocytes with docetaxel prior to vitrification reduced the expression of autophagy-related genes and increased survival and fertilization rates compared to untreated oocytes.

The implementation of artificial intelligence to the low-cost metaphase finder.

Biological dosimetry is used to estimate one's dose by biological phenomena. The most popular and 'gold standard' phenomenon is the appearance of dicentric chromosomes in metaphases. The metaphase finder is a tool for biological dosimetry that finds metaphase cells on glass slides. It consists of an automated microscope, auto-focus system, X-Y stage, camera and computer. It does the image analysis of the microscopic images of the glass slides and displays the positions of metaphase cells. In this paper, the author reported that the prototype of AI-implemented metaphase finder was combined with the microscope system by file sharing and image transfer program, and that the metaphase finder system's accuracy was compared with previous non-AI system, using the same samples.

Feasibility and efficiency of delayed ovarian stimulation and metaphase II oocyte banking for fertility preservation and childbearing desire after fertility-impairing treatment.

The aim of our study was to evaluate the feasibility and efficiency of delayed ovarian stimulation and metaphase II oocyte banking for fertility preservation after fertility-impairing treatment regardless of the initial disease. We conducted a cohort study based on population of women < 40 years of age with diminished ovarian reserve caused by fertility-impairing treatment (n = 129). Three groups of women were compared according to the type of initial disease: hematological malignancies, solid tumors, and benign diseases. The primary endpoint was the number of metaphase II oocytes collected per woman. We studied the cumulative live-birth rate per cycle with fertilized metaphase II oocyte, for women who wanted to conceive. We studied 245 delayed controlled ovarian stimulation cycles in 129 women: 201 for fertility preservation and 44 for in vitro fertilization and fresh embryo transfers. The number of metaphase II oocytes collected per woman after banking was similar in the three groups, with a mean of 10.7 ± 4.6, 12.3 ± 9.1, and 10.1 ± 7.6 metaphase II oocytes (p = 0.46), respectively. In the subgroup of women who wanted to conceive, the cumulative live birth rate per woman was 38%, with 8 live births for these 21 women. After fertility-impairing treatment, practitioners should discuss a fertility preservation procedure for banking metaphase II oocytes.