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STUDY QUESTION Does the downregulation of cell division cycle 42 (CDC42) protein in endometrial stroma lead to endometrial senescence in patients with recurrent implantation failure (RIF), and what is the potential mechanism? SUMMARY ANSWER CDC42 deficiency causes endometrial stromal senescence and decidualization defects, impairing uterine receptivity of RIF patients, via activation of Wnt signaling pathway. WHAT IS KNOWN ALREADY Uterine aging is unique due to the cyclic remodeling and decidualization of endometrial tissue. Several transcriptomic studies have reported increased senescence in the endometrium in young patients with RIF. Our previous transcriptomic sequencing study discovered that endometrium from women with RIF showed downregulation of CDC42, which is an essential molecule affected by various senescence-related diseases. STUDY DESIGN, SIZE, DURATION The endometrial samples of a total of 71 fertile control patients and 37 RIF patients were collected to verify the association between CDC42 expression and endometrial senescence of RIF patients. Primary endometrial stromal cells (EnSCs) were isolated from endometrial biopsies taken from patients without any endometrial complications and planning to undergo IVF, then subjected to adenovirus-mediated CDC42 knockdown and decidualization induction to explore the detailed mechanism by which CDC42 governs stromal senescence and decidualization. Wnt inhibitor XAV-939 was used to correct the endometrial senescence and decidualization defect. PARTICIPANTS/MATERIALS, SETTING, METHODS Senescence was determined by cell cycle arrest markers (e.g. P16, P21, and P53), SASP molecules (e.g. IL6 and CXCL8), and SA-β-gal staining. Masson's staining and Sirius Red staining were used to detect the endometrial fibrosis. Decidualization was evaluated by the mRNA expression and protein secretion of PRL and IGFBP1, F-actin immunostaining, and the BeWo spheroids ' in vitro implantation' model. Methods used to assess cell function included adenovirus transduction, RNA-sequencing, bioinformatic analysis, western blotting, RT-qPCR, ELISA, and immunofluorescence. MAIN RESULTS AND THE ROLE OF CHANCE Here, we observed remarkably increased levels of stromal senescence and fibrosis, along with stromal CDC42 deficiency, in the endometrium of patients with RIF (P  < 0.001). Knockdown of CDC42 effectively induced premature senescence in EnSCs, leading to aberrant accumulation of senescent EnSCs and collagen deposition during decidualization. CDC42 deficiency in EnSCs restrained the decidualization differentiation and receptivity to trophoblast cells. Transcriptomic analysis revealed Wnt signaling activation as a critical downstream alteration in CDC42-deficient EnSCs. Mechanistically, CDC42 interacted with AKT competitively to impede the binding of GSK3β to AKT. Knockdown of CDC42 increased AKT-mediated phosphorylation of GSK3β to inactivate the Axin-GSK3β destruction complex, leading to accumulation and nuclear translocation of β-catenin. Importantly, Wnt signaling inhibitors partially corrected the endometrial senescence caused by CDC42 deficiency, and improved both decidualization and trophoblast invasion. LARGE SCALE DATA RNA-seq data sets generated in this study have been deposited at the NCBI database with BioProject accession number PRJNA1102745. LIMITATIONS, REASONS FOR CAUTION The present study was based on in vitro cell cultures. Further studies involving CDC42-regulated endometrial senescence are needed in knockout mice model and human endometrial assembloids. WIDER IMPLICATIONS OF THE FINDINGS In addition to uncovering endometrial senescence in RIF, our findings underscore the significance of CDC42 in modulating EnSC senescence to maintain the decidualization function, and suggest Wnt signaling inhibitors as potential therapeutic agents for alleviating endometrial senescence. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the National Natural Science Foundation of China [82271698 (R.J.), 82030040 (H.S.), 82288102 (H.W.), and 82371680 (G.Y.)]; the Natural Science Foundation of Jiangsu Province [BK20231117 (R.J.)]; and the Medical Science and Technology Development Foundation of Nanjing Department of Health [YKK23097 (Y.Z.)]. The authors declare no potential conflicts of interest. [ABSTRACT FROM AUTHOR]

Major zygotic genome activation (ZGA) occurs at the late 2‐cell stage and involves the activation of thousands of genes, supporting early embryonic development. The reasons underlying the regulation of ZGA are not clear. Acetylation modifications of histone tails promote transcriptional activation, and the maternal deletion of H4K16ac leads to failure in ZGA. GATAD2B is one of the core subunits of the nucleosome remodelling and histone deacetylation (NuRD) complex. Our research has shown that GATAD2B exhibits specific nucleus localization and high protein expression from the late 2‐cell stage to the 8‐cell stage. This intriguing phenomenon prompted us to investigate the relationship between GATAD2B and the ZGA. We discovered a distinctive pattern of GATAD2B, starting from the late 2‐cell stage with nuclear localization. GATAD2B depletion resulted in defective embryonic development, including increased DNA damage at morula, decreased blastocyst formation rate, and abnormal differentiation of ICM/TE lineages. Consistent with the delay during the cleavage stage, the transcriptome analysis of the 2‐cell embryo revealed inhibition of the cell cycle G2/M phase transition pathway. Furthermore, the GATAD2B proteomic data provided clear evidence of a certain association between GATAD2B and molecules involved in the cell cycle pathway. As hypothesized, GATAD2B‐deficient 2‐cell embryos exhibited abnormalities in ZGA during the maternal‐to‐embryonic transition, with lower expression of the major ZGA marker MERVL. Overall, our results demonstrate that GATAD2B is essential for early embryonic development, in part through facilitating ZGA. [ABSTRACT FROM AUTHOR]

Despite the importance of data reduction as part of the processing of reflection-based classifications, this study represents one of the first in which the effects of both spatial and spectral data reductions on classification accuracies are quantified. Furthermore, the effects of approaches to data reduction were quantified for two separate classification methods, linear discriminant analysis (LDA) and support vector machine (SVM). As the model dataset, reflection data were acquired using a hyperspectral camera in 230 spectral channels from 401 to 879 nm (spectral resolution of 2.1 nm) from field pea (Pisum sativum) samples with and without internal pea weevil (Bruchus pisorum) infestation. We deployed five levels of spatial data reduction (binning) and eight levels of spectral data reduction (40 datasets). Forward stepwise LDA was used to select and include only spectral channels contributing the most to the separation of pixels from non-infested and infested field peas. Classification accuracies obtained with LDA and SVM were based on the classification of independent validation datasets. Overall, SVMs had significantly higher classification accuracies than LDAs (P < 0.01). There was a negative association between pixel resolution and classification accuracy, while spectral binning equivalent to up to 98% data reduction had negligible effect on classification accuracies. This study supports the potential use of reflection-based technologies in the quality control of food products with internal defects, and it highlights that spatial and spectral data reductions can (1) improve classification accuracies, (2) vastly decrease computer constraints, and (3) reduce analytical concerns associated with classifications of large and high-dimensional datasets.

In this study, we acquired 72 (training data) and 30 (independent validation) high-spatial resolution (7 by 7 pixels per mm2) hyperspectral imaging data [240 spectral bands from 392 to 889 nm (spectral resolution = 2.1 nm)] from samples of field peas (Pisum sativum) with and without pea weevil (Bruchus pisorum) infestation. The reflectance data were analyzed with linear discriminant analysis (LDA) or either reflectance values only or of a combination of reflectance values and variogram parameters (derived from variogram analysis) from a single spectral band (782 nm). All examined classification models were assessed based on sensitivity (ability to positively detect infestation), specificity (ability to positively detect non-infestation), and accurate classification of 30 samples of independent validation data. Highest classification performance was obtained with a combination of reflectance values in two spectral bands (641 nm and 868 nm) and variogram parameters derived from 782 nm. This classification model was associated with a sensitivity of 94.7% and a specificity of 100%. In addition, all 30 independent validation data were accurately classified (100%). For comparison, traditional linear discriminant analyses of 108,351 reflectance profiles from individual pixels in the 72 samples or average reflectance profiles from the 72 samples classified the validation data with 84.0% and 83.3% accuracy, respectively. We are unaware of any reflectance-based classification system, which - based on reflectance data acquired in only three channels (spectral bands) - can provide this level of sensitivity and specificity and classification of independent validation data of internal defects in food products. Accurate and reliable classification of food objects based reflectance values in only a few spectral bands would likely imply low computer processing requirements and rapid data analysis. Thus, we believe that the current classification method may be useful for quality control systems of a wide range of food products. © 2013 Elsevier Ltd. All rights reserved.

STUDY QUESTION Does abnormal serotonin homeostasis contribute to impaired endometrial decidualization in patients with recurrent implantation failure (RIF)? SUMMARY ANSWER Abnormal serotonin homeostasis in patients with RIF, which is accompanied by decreased monoamine oxidase (MAO) expression, affects the decidualization of endometrial stromal cells and leads to embryo implantation failure. WHAT IS KNOWN ALREADY Previous studies have indicated that the expression of MAO, which metabolizes serotonin, is reduced in the endometrium of patients with RIF, and serotonin can induce disruption of implantation in rats. However, whether abnormal serotonin homeostasis leads to impaired decidualization in patients with RIF and, if so, the mechanism involved, remains unclear. STUDY DESIGN, SIZE, DURATION Endometrial samples from 25 patients with RIF and 25 fertile patients were used to investigate the expression levels of monoamine oxidase A (MAOA), monoamine oxidase B (MAOB), and serotonin. We isolated human endometrial stromal cells to investigate the role of MAOA, MAOB, and serotonin in inducing decidualization in vitro and further explored the underlying mechanism using RNA-sequencing (RNA-seq) and liquid chromatography-mass spectrometry (LC/MS) analyses. PARTICIPANTS/MATERIALS, SETTING, METHODS The levels of serotonin in the endometrium of patients with RIF were detected by ELISA and immunohistofluorescence, and the key genes involved in abnormal serotonin metabolism were analyzed via combination with single-cell sequencing data. The effects of MAOA or MAOB on the decidualization of stromal cells were investigated using an in vitro human endometrial stromal cell-induced decidualization model and a mouse artificially induced decidualization model. The potential mechanisms by which MAOA and MAOB regulate decidualization were explored by RNA-seq and LC/MS analysis. MAIN RESULTS AND THE ROLE OF CHANCE We found that women with RIF have abnormal serotonin metabolism in the endometrium and attenuated MAO in endometrial stromal cells. Endometrial decidualization was accompanied by increased MAO in vivo and in vitro. However attenuated MAO caused an increased local serotonin content in the endometrium, impairing stromal cell decidualization. RNA-seq and LC/MS analyses showed that abnormal lipid metabolism, especially phosphatidylcholine metabolism, was involved in the defective decidualization caused by MAO deficiency. Furthermore, decidualization defects were rescued by phosphatidylcholine supplementation. LARGE SCALE DATA RNA-seq information and raw data can be found at NCBI Bioproject number PRJNA892255. LIMITATIONS, REASONS FOR CAUTION This study revealed that impaired serotonin metabolic homeostasis and abnormally reduced MAO expression were among the reasons for RIF. However, the source and other potential functions of serotonin in the endometrium remain to be further explored. WIDER IMPLICATIONS OF THE FINDINGS This study provides new insights into the mechanisms of serotonin homeostasis in human endometrial decidualization and new biomarkers or targets for the treatment of patients with RIF. STUDY FUNDING/COMPETING INTEREST(S) X. Sheng is supported by grants from the National Natural Science Foundation of China (82001629), the Wenzhou Basic Public Welfare Research Project (Y20240030), the Youth Program of Natural Science Foundation of Jiangsu Province (BK20200116), and Jiangsu Province Postdoctoral Research Funding (2021K277B). H.S. is supported by grants from the National Natural Science Foundation of China (82030040). G.Y. is supported by grants from the National Natural Science Foundation of China (82171653). The authors declare no conflicts of interest. [ABSTRACT FROM AUTHOR]