Search

During in vitro maturation, excess levels of reactive oxygen species (ROS) are a major cause of developmental defects in embryos. Betulinic acid (BA) is a naturally produced antioxidant in white birch bark. Recent studies have shown that BA exhibits antioxidant properties in various cells through the activation of antioxidant genes. Therefore, we investigated the effect of BA treatment on porcine oocytes and its underlying mechanism during oocyte maturation. Treatment with 0.1 μM BA significantly increased the proportion of MII oocytes compared with controls, and BA-treated oocytes had significantly higher development rates, trophectoderm cell numbers, and cell survival rates than controls. These results demonstrate that BA treatment improved the developmental competence of oocytes. Following BA treatment, oocytes exhibited reduced ROS levels and elevated glutathione (GSH) levels, accompanied by the enhanced expression of antioxidant genes, compared with control oocytes. To evaluate the antioxidant effects of BA, oocytes were exposed to H2O2, a potent ROS activator. Impaired nuclear maturation, ROS levels, and GSH levels induced in oocytes by H2O2 exposure was restored by BA treatment. As these antioxidant genes are regulated by the Nrf2/Keap1 signaling pathway, which is involved in antioxidant responses, we applied the Nrf2 inhibitor brusatol to investigate the effects of BA on this pathway. The negative effects of brusatol on meiotic maturation and oocyte quality, including levels of ROS, GSH, and antioxidant-related gene expression, were mitigated by BA treatment. Our results suggested that BA plays an effective role as an antioxidant in porcine oocyte maturation through adjusting the Nrf2/Keap1 signaling pathway. This finding provides valuable insights into the mechanisms governing oocyte maturation and embryonic development. [ABSTRACT FROM AUTHOR]

NIMA‐related kinase 2 (NEK2) is a serine/threonine protein kinase that regulates mitosis and plays pivotal roles in cell cycle regulation and DNA damage repair. However, its function in porcine embryonic development is unknown. In this study, we used an NEK2‐specific inhibitor, JH295 (JH), to investigate the role of NEK2 in embryonic development and the underlying regulatory mechanisms. Inhibition of NEK2 after parthenogenesis activation or in vitro fertilization significantly reduced the rates of cleavage and blastocyst formation, the numbers of trophectoderm and total cells and the cellular survival rate compared with the control condition. NEK2 inhibition delayed cell cycle progression at all stages from interphase to cytokinesis during the first mitotic division; it caused abnormal nuclear morphology in two‐ and four‐cell stage embryos. Additionally, NEK2 inhibition significantly increased DNA damage and apoptosis, and it altered the expression levels of DNA damage repair‐ and apoptosis‐related genes. Intriguingly, NEK2 inhibition downregulated the expression of β‐catenin and its downstream target genes. To validate the relationship between Wnt/β‐catenin signalling and NEK2 during porcine embryonic development, we cultured porcine embryos in JH‐treated medium with or without CHIR99021, a Wnt activator. CHIR99021 co‐treatment strongly restored the developmental parameters reduced by NEK2 inhibition to control levels. Our findings suggest that NEK2 plays an essential role in porcine embryonic development by regulating DNA damage repair and normal mitotic division via the Wnt/β‐catenin signalling pathway. [ABSTRACT FROM AUTHOR]

SiNx thin films have garnered attention as promising barrier films, primarily due to their low impurity diffusion rates, making them suitable for various technological applications. Despite their potential, these films face challenges because they are prone to degradation in hostile environments. This study investigated the oxidation behavior of SiNx thin films, particularly when deposited on two different types of substrates: rigid silicon (Si) and flexible polyethylene terephthalate (PET) films. A thorough microstructural analysis of the SiNx films reveals their detailed morphological and compositional characteristics, enabling a comparison between the SiNx/Si and SiNx/PET films. This study further investigates the impacts of high-temperature and humidity exposure on SiNx thin films, systematically elucidating the degradation behaviors and underlying mechanisms. The structural evolution during SiNx film oxidation is illustrated at the nanoscale, and the factors contributing to the oxidation were analyzed. This study deepens our understanding of the interplay between oxidation processes and the unique environmental conditions of substrates, offering insights into enhancing the stability and reliability of these materials. [ABSTRACT FROM AUTHOR]

Roll‐to‐roll (R2R) fabrication of high‐performance perovskite solar cells (PSCs) remains challenging for PSC commercialization. Herein, the R2R‐suitable electron transfer layer (ETL) SnO2 ink system for flexible PSCs is investigated. Water‐dispersed SnO2 inks, commonly used for flexible PSCs, form dewetting pinholes during R2R slot‐die coating owing to slower evaporation compared to spin coating. To prevent the dewetting of the pinhole, a low surface tension solvent (isopropyl alcohol, IPA) is added to the SnO2 ink. The IPA addition reduced surface tension, enhancing wetting behavior, but increased SnO2 nanoparticles (NPs) aggregation. Interestingly, the fabricated ETL films with highly aggregated SnO2 NPs are smooth, in contrast to the rough layers obtained via the spin‐coating process, owing to the high shear rate. Herein, NP aggregation and surface morphology are explored using Brownian dynamics simulations under shear conditions. Consequently, when the particles are agglomerated, the PSCs with slot‐die coating exhibit higher power conversion efficiency compared to ETL spin‐coated PSCs. Therefore, IPA addition to SnO2 ink is preferred for the R2R slot‐die process by improving the wetting properties and forming smooth films. In this study, a framework is provided for obtaining high‐quality films using the slot‐die coating of ETL and promotes the commercialization of PSCs. [ABSTRACT FROM AUTHOR]

The technological requirements are changing, and there is a push for more effective energy production and conversion technologies as a result of a social desire for sustainable and renewable energy sources. Solar energy conversion, particularly photovoltaic cells, offers a potentially helpful solution in this situation. Power conversion efficiency (PCE) of perovskite solar cells (PSCs) has been reported to have increased significantly from 3% to 26.1%. The transition from laboratory PSCs to their commercialization needs scalable deposition techniques, high efficiency at a scalable level, and perovskite photovoltaic with minimal loss in PCE. In this review article, the scalable fabrication processes for perovskite solar modules (PSMs) and their fabrication challenges, as well as latest developments in PSM stability, are focused on. Finally, the future prospectus and challenges for PSMs are presented. This review will give us an overall understanding of the thin film coating inside the PSM and good insight into the future direction of development. [ABSTRACT FROM AUTHOR]

Abstract Many important molecular events associated with implantation and development occur within the female reproductive tract, especially within the uterus endometrium, during pregnancy periods. The endometrium includes the mucosal lining of the uterus, which provides a suitable site for implantation and development of a fertilized egg and fetus. To date, the molecular cascades in the uterus endometrium during pregnancy periods in pigs have not been elucidated fully. In this study, we compared the functional regulated proteins in the endometrium during pregnancy periods with those in non-pregnant conditions and investigated changes in expression patterns during pregnancy (days 40, 70, and 93) using two-dimensional gel electrophoresis (2-DE) and western blotting. The functional regulated proteins were identified and discovered from differentially expressed proteins in the uterus endometrium during pregnancy. We discovered 820 protein spots in a proteomic analysis of uterus endometrium tissues with 2-DE gels. We identified 63 of the 98 proteins regulated differentially among non-pregnant and pregnant tissues (matched and unmatched spots). Interestingly, 10 of these 63 proteins are development-, cytoskeleton- and chaperon-related proteins such as transferrin, protein DJ-1, transgelin, galectin-1, septin 2, stathmin 1, cofilin 1, fascin 1, heat shock protein (HSP) 90β and HSP 27. The specific expression patterns of these proteins in the endometrium during pregnancy were confirmed by western blotting. Our results suggest that the expressions of these genes involved in endometrium function and endometrium development from early to late gestation are associated with the regulation of endometrium development for maintaining pregnancy.

Abstract Background Somatic cell nuclear transfer (scNT)-derived piglets have high rates of mortality, including stillbirth and postnatal death. Here, we examined severe malformed umbilical cords (MUC), as well as other organs, from nine scNT-derived term piglets. Results Microscopic analysis revealed complete occlusive thrombi and the absence of columnar epithelial layers in MUC (scNT-MUC) derived from scNT piglets. scNT-MUC had significantly lower expression levels of platelet endothelial cell adhesion molecule-1 (PECAM-1) and angiogenesis-related genes than umbilical cords of normal scNT piglets (scNT-N) that survived into adulthood. Endothelial cells derived from scNT-MUC migrated and formed tubules more slowly than endothelial cells from control umbilical cords or scNT-N. Proteomic analysis of scNT-MUC revealed significant down-regulation of proteins involved in the prevention of oxidative stress and the regulation of glycolysis and cell motility, while molecules involved in apoptosis were significantly up-regulated. Histomorphometric analysis revealed severe calcification in the kidneys and placenta, peliosis in the liver sinusoidal space, abnormal stromal cell proliferation in the lungs, and tubular degeneration in the kidneys in scNT piglets with MUC. Increased levels of apoptosis were also detected in organs derived from all scNT piglets with MUC. Conclusion These results suggest that MUC contribute to fetal malformations, preterm birth and low birth weight due to underlying molecular defects that result in hypoplastic umbilical arteries and/or placental insufficiency. The results of the current study demonstrate the effects of MUC on fetal growth and organ development in scNT-derived pigs, and provide important insight into the molecular mechanisms underlying angiogenesis during umbilical cord development.