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The unique patterns of epigenetic modifications appear in mammalian oocyte development. Establishment of these modifications, including DNA methylation and histone modifications, is a complicated but highly ordered process, which is crucial in terms of oocyte maturation and early embryo development in mammals. Therefore, dissecting the mechanisms of epigenetic establishment in oocytes is of great significance to look insight into the principles of reproduction and pathogenesis of related diseases. In this review, we delineate the distribution patterns and dynamic landscapes of DNA methylation as well as histone methylation, acetylation, ubiquitination, phosphorylation and lactylation in mammalian oocyte development represented by mice and humans. Meanwhile, we present a summary and discussion in the matter of the potential relevance among these epigenetic modifications, which are regulated by multiple factors related to biological functions.

The protective effects of pigment epithelium-derived factor (PEDF) against X-ray-induced retinopathy were investigated in vitro and in vivo. The function of PEDF was suppressed using PEDF receptor inhibitors and transfection of siRNA in human retinal pigment epithelium cell line ARPE-19. The decreased expression of PEDF was measured using quantitative fluorescent reverse transcription PCR and ELISA. Cell viability after X-ray exposure was monitored using the CCK-8 method. Both left and right irradiation fields were set up to deliver X-rays to the eyes of mice using a small animal radiotherapy simulation machine. Each field was irradiated with 10 Gy. The total dose was 20 Gy. The saline containing 2 nmol/L PEDF-34, a 34-amino acid fragment at positions 44~77 of the PEDF, was prepared. After irradiation, the mice were treated with eye drops every day for 4 weeks. After 8 weeks, the eyeballs were harvested for HE and TUNEL staining and checked for retinopathy and apoptosis. The results showed that pretreatment via PEDF receptor inhibitors and the reduction of PEDF expression aggravated X-ray-induced cell damage in ARPE-19 cells, while PEDF-34 exerted protective effects against X-ray-induced cell damage. Eight weeks after irradiation with a dose of 20 Gy, the experimental mice demonstrated aberrant morphology in the retinal pigment epithelial cell layer and apoptotic cells in the outer nuclear layer. The PEDF-34-treated group maintained a structurally normal retina and had no apoptotic cells. The current study indicates that PEDF has a protective effect against radiation-induced retinopathy, and the PEDF-34-containing eye drops could alleviate the injury. Our findings may provide an experimental basis for a new treatment approach for radiation retinopathy.

In order to investigate the laws of the laser peening forming process and the effects of laser peening on the surface quality and tensile properties of 5083 aluminum alloy, experiments were conducted utilizing various laser peening paths, energies, and plate thicknesses. Subsequently, laser peening forming experiments were performed on S-shaped and different shapes of aluminum alloy substrates. The impact of different laser peening durations on surface morphology and tensile properties was then analyzed. Results indicated that the largest bending deformation perpendicular to the laser peening path reached 12.5 mm. In cases where the laser peening path was inclined relative to the horizontal direction, torsional deformations were observed in the aluminum alloy plate. For laser energy levels of 5 J, 6 J, and 7 J, deformation amounts were 3.8 mm, 4.9 mm, and 5.4 mm, respectively. Plates with thicknesses of 4 mm exhibited convex deformation, while those with 2 mm thickness showed concave deformation. Furthermore, following one and two laser peening cycles, the residual stresses in the alloy plates were −80 MPa and −107 MPa, the surface hardness increased by 16 HV and 31 HV, the roughness increased by 2.495 μm and 3.615 μm, and the tensile strength increased by 9.5 MPa and 18.5 MPa, respectively. [ABSTRACT FROM AUTHOR]

This study examines the climatic characteristics of 202 Jianghuai cyclones and their linkage with precipitation during the Meiyu period from 1961 to 2020. The results show that cyclones mainly originate from the eastern and western Hubei Province. Additionally, we explore the statistical characteristics of intensity, radius and their positive correlation. In studying the decadal variation of cyclones, we find a similar evolution between the cyclones and Meiyu precipitation. Therefore, we further investigate the correlation between the Jianghuai cyclones and the precipitation during the Meiyu period. There is a positive correlation coefficient of 0.77 between them. Notably, the percentage of precipitation affected by cyclone activities can reach up to 47 %. The anomalous increase in precipitation caused by cyclones north of 27° N can reach a maximum of 7 mm d -1. When a cyclone exists, a significant negative geopotential height anomaly at the 500 hPa level over Mongolia can be traced back to day -4. The abnormally enhanced WPSH (western Pacific subtropical high), southwesterly low-level jet and negative geopotential height are the dominant factors causing abnormal precipitation during Jianghuai cyclones. Before and after the cyclone develops, water vapor flux and divergence from low latitudes increase abnormally, providing sufficient water vapor conditions for the generation of cyclone precipitation. [ABSTRACT FROM AUTHOR]

Ag-TiO2 photocatalysts with different doping concentration were prepared by sol-gel method using tetrabutyl titanate and silver nitrate as raw materials. The crystal structure, surface morphology, chemical composition, optical properties of the samples were characterized by XRD, SEM, XPS, DRS and PL, respectively. The photocatalytic activity of xAg-TiO2(x=1%,2%,4%,6%,atom fraction) under UV light and simulated sunlight was evaluated by the degradation of Rhodamine B by using mercury lamp and xenon lamp as the light source, respectively. The results indicate that the photocatalytic activity of TiO2 under UV light and simulated sunlight enhances as the recombination rate of photogenerated electron-hole decreases and the absorption of simulated sunlight increases by Ag doping. 1%Ag-TiO2 exhibits the best photocatalytic activity. The degradation rates of Rhodamine B are 91% under UV light and 89% under simulated sunlight, which are 1.18 and 1.24 times higher than that of pure TiO2. The reaction rate constants are 0.01257 min-1 and 0.01150 min-1, which are 1.49 and 1.74 times higher than that of pure TiO2.

Nitrous acid (HONO) and nitrogen oxides (NOx = NO + NO2) are important atmospheric pollutants and key intermediates in the global nitrogen cycle, but their sources and formation mechanisms are still poorly understood. Here, we investigated the effect of soluble iron (Fe3+) on the photochemical behaviour of a widely used neonicotinoid (NN) insecticide, nitenpyram (NPM), in the aqueous phase. The yields of HONO and NOx increased significantly when NPM solution was irradiated in the presence of iron ions (Fe3+). We propose that the enhanced HONO and NO2 emissions from the photodegradation of NPM in the presence of iron ions result from the redox cycle between Fe3+ and Fe2+ and the generated reactive oxygen species (ROS) by the electron transfer between the excited triplet state of NPM and the molecular oxygen O2). Using the laboratory-derived parametrization based on kinetic data and gridded downward solar radiation, we estimate that the photochemistry of NPM induced by Fe3+ releases 0.50 and 0.77 Tg N year-1 of NOx and HONO to the atmosphere, respectively. This study suggests a novel source of HONO and NOx during daytime and potentially helps to narrow the gap between the field observations and model outcomes of HONO in the atmosphere. The suggested photochemistry of NPM can be an important contribution to the global nitrogen cycle affecting the atmospheric oxidizing capacity as well as the climate change. [ABSTRACT FROM AUTHOR]

Background: To analyze vault effects of crystalline lens rise (CLR) and anterior chamber parameters (recorded by Pentacam) in highly myopic patients receiving implantable collamer lenses (ICLs), which may avoid subsequent complications such as glaucoma and cataract caused by the abnormal vault. Methods: We collected clinical data of 137 patients with highly myopic vision, who were all subsequent recipients of V4c ICLs between June 2020 and January 2021. Horizontal ciliary sulcus-to-sulcus diameter (hSTS) and CLR were measured by ultrasonic biomicroscopy (UBM), and a Pentacam anterior segment analyzer was used to measure horizontal white-to-white diameter (hWTW), anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV), CLR, and postoperative vault (Year 1 and Month 1). The lens thickness (LT) was determined by optical biometry (IOL Master instrument). The predictive model was generated through multiple linear regression analyses of influential factors, such as hSTS, CLR, hWTW, ACD, ACA, ACV, ICL size, and LT. The predictive performance of the multivariate model on vault after ICL was assessed using the receiver operating characteristic (ROC) curve with area under the curve (AUC) as well as the point of tangency. Results: Average CLR assessed by UBM was lower than the average value obtained by Pentacam (0.561 vs. 0.683). Bland-Altman analysis showed a good consistency in the two measurement methods and substantial correlation (r = 0.316; P = 0.000). The ROC curve of Model 1 (postoperative Year 1) displayed an AUC of 0.847 (95% confidence interval [CI]: 74.19–95.27), with optimal threshold of 0.581 (sensitivity, 0.857; specificity, 0.724). In addition, respective values for Model 2 (postoperative Month 1) were 0.783 (95% CI: 64.94–91.64) and 0.522 (sensitivity, 0.917; specificity, 0.605). Conclusion: CLR and anterior chamber parameters are important determinants of postoperative vault after ICL placement. The multivariate regression model we constructed may serve in large part as a predictive gauge, effectively avoid postoperative complication. [ABSTRACT FROM AUTHOR]

Non-human primates (NHPs) are increasingly used in preclinical trials to test the safety and efficacy of biotechnology therapies. Nonetheless, given the ethical issues and costs associated with this model, it would be highly advantageous to use NHP cellular models in clinical studies. However, developing and maintaining the naïve state of primate pluripotent stem cells (PSCs) remains difficult as does in vivo detection of PSCs, thus limiting biotechnology application in the cynomolgus monkey. Here, we report a chemically defined, xeno-free culture system for culturing and deriving monkey PSCs in vitro. The cells display global gene expression and genome-wide hypomethylation patterns distinct from monkey-primed cells. We also found expression of signaling pathways components that may increase the potential for chimera formation. Crucially for biomedical applications, we were also able to integrate bioluminescent reporter genes into monkey PSCs and track them in chimeric embryos in vivo and in vitro. The engineered cells retained embryonic and extra-embryonic developmental potential. Meanwhile, we generated a chimeric monkey carrying bioluminescent cells, which were able to track chimeric cells for more than 2 years in living animals. Our study could have broad utility in primate stem cell engineering and in utilizing chimeric monkey models for clinical studies. [ABSTRACT FROM AUTHOR]

Ag-TiO2 photocatalysts with different doping concentration were prepared by sol-gel method using tetrabutyl titanate and silver nitrate as raw materials. The crystal structure, surface morphology, chemical composition, optical properties of the samples were characterized by XRD, SEM, XPS, DRS and PL, respectively. The photocatalytic activity of xAg-TiO2(x=1%,2%,4%,6%,atom fraction) under UV light and simulated sunlight was evaluated by the degradation of Rhodamine B by using mercury lamp and xenon lamp as the light source, respectively. The results indicate that the photocatalytic activity of TiO2 under UV light and simulated sunlight enhances as the recombination rate of photogenerated electron-hole decreases and the absorption of simulated sunlight increases by Ag doping. 1%Ag-TiO2 exhibits the best photocatalytic activity. The degradation rates of Rhodamine B are 91% under UV light and 89% under simulated sunlight, which are 1.18 and 1.24 times higher than that of pure TiO2. The reaction rate constants are 0.01257 min-1 and 0.01150 min-1, which are 1.49 and 1.74 times higher than that of pure TiO2.

Ruthenium (Ru) has been recognized as a prospective candidate to substitute platinum catalysts in water‐splitting‐based hydrogen production. However, minimizing the Ru contents, optimizing the water dissociation energy of Ru sites, and enhancing the long‐term stability are extremely required, but still face a great challenge. Here, we report on creating tungsten oxide‐anchored Ru clusters (Ru–WOx) with electron‐rich and anti‐corrosive microenvironments for efficient and robust seawater splitting. Benefiting from the abundant oxygen vacancy structure in tungsten oxide support, the Ru–WOx exhibits strong Ru–O and Ru–W bonds at the interface. Our study elucidates that the strong Ru–O bonds in Ru–WOx may accelerate the water dissociation kinetics, and the Ru–W bonds will lead to the strong metal–support interaction and electrons transfer from W to Ru. The optimal Ru–WOx catalysts exhibit a low overpotential of 29 and 218 mV at the current density of 10 mA cm−2 in alkaline and seawater media, respectively. The outstanding long‐term stability discloses that the Ru–WOx catalysts own efficient corrosion resistance in seawater electrolysis. We believe that this work offers new insights into the essential roles of electron‐rich and anti‐corrosive microenvironments in Ru‐based catalysts and provide a new pathway to design efficient and robust cathodes for seawater splitting. [ABSTRACT FROM AUTHOR]

Background: At present, a diagnostic tool with high specificity for impaired endometrial receptivity, which may lead to implantation failure, remains to be developed. We aimed to assess the different endometrial microRNA (miRNA) signatures for impaired endometrial receptivity by microarray analysis. Methods: A total of 12 repeated implantation failure (RIF) patients and 10 infertile patients, who conceived and delivered after one embryo transfer attempt, were recruited as RIF and control groups, respectively. Endometrial specimens from the window of implantation (WOI) were collected from these two groups. MiRNA microarray was conducted on seven and five samples from the RIF and control groups, respectively. Comparative, functional, and network analyses were performed for the microarray results. Quantitative real-time polymerase chain reaction (PCR) was performed on other samples to validate the expression of specific miRNAs. Results: Compared with those in the control group, the expression levels of 105 miRNAs in the RIF group were found to be significantly up- or down-regulated (at least 2-fold) by microarray analysis. The most relevant miRNA functional sets of these dysregulated miRNAs were miR-30 family, human embryonic stem cell regulation, epithelial-mesenchymal transition, and miRNA tumor suppressors by tool for annotations of microRNA analysis. Network regulatory analysis found 176 miRNA-mRNA interactions, and the top 3 core miRNAs were has-miR-4668-5p, has-miR-429, and has-miR-5088. Expression levels of the 18 selected miRNAs in new samples by real-time PCR were found to be regulated with the same trend, as the result of microarray analysis. Conclusions: There is a significant different expression of certain miRNAs in the WOI endometrium for RIF patients. These miRNAs may contribute to impaired endometrial receptivity.

Overexpression of receptor-interacting protein 140 (RIP140) promotes neuronal differentiation of N2a cells via extracellular regulated kinase 1/2 (ERK1/2) signaling. However, involvement of RIP140 in human neural differentiation remains unclear. We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells. Moreover, RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation, and positively correlated with the neural stem cell marker Nestin during later stages. Thus, ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.