Curvature-Induced Electron Delocalization Activates the Bifunctional Catalytic Activity of COF/MXene for High-Performance Lithium-Sulfur Batteries.

Covalent organic frameworks (COFs) have shown promise as bifunctional catalysts to simultaneously mitigate shuttle effects and Li dendrite issues of lithium-sulfur (Li-S) batteries. However, the inherent low conductivity of the COFs has significantly limited their catalytic activity and stability. Herein, bifunctional catalytic activity and durability of the COF/MXene heterostructure are activated by tuning the surface curvatures of COFs interfaced with MXene.

Duplex Unwinding Mechanism of Coronavirus MERS-CoV nsp13 Helicase.

The COVID-19 pandemic has underscored the importance of in-depth research into the proteins encoded by coronaviruses (CoV), particularly the highly conserved nonstructural CoV proteins (nsp). Among these, the nsp13 helicase of severe pathogenic MERS-CoV, SARS-CoV-2, and SARS-CoV is one of the most preserved CoV nsp. Utilizing single-molecule FRET, we discovered that MERS-CoV nsp13 unwinds DNA in distinct steps of about 9 bp when ATP is employed.

Activation of the bacterial defense-associated sirtuin system.

The NADase activity of the defense-associated sirtuins (DSRs) is activated by the phage tail tube protein (TTP). Herein, we report cryo-EM structures of a free-state Bacillus subtilis DSR2 tetramer and a fragment of the tetramer, a phage SPR tail tube, and two DSR2-TTP complexes. DSR2 contains an N-terminal SIR2 domain, a middle domain (MID) and a C-terminal domain (CTD).

Preparation and Characterization of Lightweight, Hydrophobic, and Insulative Melamine Foam/Fumed Silica Composites.

Nanoparticulate silica is renowned for its excellent thermal insulation and low density; however, it faces challenges in practical applications due to high production costs and poor mechanical properties. In this study, a lightweight, hydrophobic, and insulative composite consisting of fumed silica and melamine foam (MF-FS) was prepared by using an atmospheric impregnation and drying process. Four different concentrations of fumed silica (5, 10, 15, and 20%) were systematically incorporated into the melamine foam to assess their effects on the composite's performance.

Superior Active and Durable Air Electrode for Protonic Ceramic Cells by Metal-Oxide Bond Engineering.

Protonic ceramic cells (PCCs) have been identified as promising energy conversion devices, offering flexible fuel options and reduced operating consumption at intermediate temperatures. However, the application of traditional cobalt-based perovskite air electrodes in PCCs is hindered by their insufficient durability and high coefficient of thermal expansion. In this study, a straightforward metal-oxygen bond engineering is conducted, introducing a single-phase perovskite, BaLa(FeZn)NO (BLFZN0.

MT1/cAMP/PKA Pathway in Melatonin-Regulated Sperm Capacitation.

Melatonin is mainly synthesized and secreted by pineal gland, and plays multiple functions, including its regulating effects on reproductive processes. Sperm capacitation is necessary for fertilization, but the effect of melatonin on mouse sperm capacitation remains to be elucidated. We thus investigated the roles of melatonin on capacitation by culturing the sperms from mouse cauda epididymis in the medium with different doses of melatonin.

Tough and Stretchable Zwitterionic Eutectogels via Copolymerization-Induced Phase Separation in a Targeted Deep Eutectic Solvent.

Deep eutectic solvent (DES)-based eutectogels show significant promise for flexible sensors due to their high ionic conductivity, non-volatility, biocompatibility, and cost-effectiveness. However, achieving tough and stretchable eutectogels is challenging, as the highly polar DES tends to screen noncovalent bonds, such as hydrogen and ionic bonds, between polymer chains, limiting their mechanical strength. In this work, this issue is addressed by leveraging the limited solubility of zwitterionic polymers in a specific DES to induce phase separation, promoting dipole-dipole interactions between polymer chains.

Computational Insights into Acrylamide Fragment Inhibition of SARS-CoV-2 Main Protease.

The pathogen of COVID-19, SARS-CoV-2, has caused a severe global health crisis. So far, while COVID-19 has been suppressed, the continuous evolution of SARS-CoV-2 variants has reduced the effectiveness of vaccines such as mRNA-1273 and drugs such as Remdesivir. To uphold the effectiveness of vaccines and drugs prior to potential coronavirus outbreaks, it is necessary to explore the underlying mechanisms between biomolecules and nanodrugs.

BCAS2 and hnRNPH1 orchestrate alternative splicing for DNA double-strand break repair and synapsis in meiotic prophase I.

Understanding the intricacies of homologous recombination during meiosis is crucial for reproductive biology. However, the role of alternative splicing (AS) in DNA double-strand breaks (DSBs) repair and synapsis remains elusive. In this study, we investigated the impact of conditional knockout (cKO) of the splicing factor gene Bcas2 in mouse germ cells, revealing impaired DSBs repair and synapsis, resulting in non-obstructive azoospermia (NOA).

Electrocatalysts for the Formation of Hydrogen Peroxide by Oxygen Reduction Reaction.

Hydrogen peroxide (HO) is a widely used strong oxidant, and its traditional preparation methods, anthraquinone method, and direct synthesis method, have many drawbacks. The method of producing HO by two-electron oxygen reduction reaction (2e ORR) is considered an alternative strategy for the traditional anthraquinone method due to its high efficiency, energy saving, and environmental friendliness, but it remains a big challenge. In this review, we have described the mechanism of ORR and the principle of electrocatalytic performance testing, and have summarized the standard performance evaluation techniques for electrocatalysts to produce HO.

Study on the Influence of Injection Velocity on the Evolution of Hole Defects in Die-Cast Aluminum Alloy.

Aluminum alloy die casting has achieved rapid development in recent years and has been widely used in all walks of life. However, due to its high pressure and high-speed technological characteristics, avoiding hole defects has become a problem of great significance in aluminum alloy die casting production. In this paper, the filling visualization dynamic characterization experiment was innovatively developed, which can directly study and analyze the influence of different injection rates on the formation and evolution of alloy flow patterns and gas-induced defects.

Taurine is essential for mouse uterine luminal fluid resorption during implantation window via the SCNN1A and AQP8 signaling†.

Uterine fluid homeostasis during peri-implantation is crucial for successful embryo implantation. Taurine (Tau) plays a crucial role in regulating osmotic pressure and ion transport. However, the precise mechanisms underlying Tau-mediated regulation of uterine fluid homeostasis during peri-implantation in mice remain unclear.

Identification of novel small-molecule inhibitors of SARS-CoV-2 by chemical genetics.

There are only eight approved small molecule antiviral drugs for treating COVID-19. Among them, four are nucleotide analogues (remdesivir, JT001, molnupiravir, and azvudine), while the other four are protease inhibitors (nirmatrelvir, ensitrelvir, leritrelvir, and simnotrelvir-ritonavir). Antiviral resistance, unfavourable drug‒drug interaction, and toxicity have been reported in previous studies.

Geometric and Electronic Structure Modulation to Optimize the Charge Transfer of TiO for Ultrasensitive and Stable SERS Sensing.

Exploring the relationship between semiconductor structure and surface-enhanced Raman scattering (SERS) activity was essential for the development of ultrasensitive SERS substrates. Herein, we report an ytterbium atomic doping strategy to render TiO (Yb-TiO) highly SERS sensitive superior to pure TiO, with a detection limit as low as 1 × 10 M for 4-mercaptobenzoic acid. First-principles density functional theory calculations reveal that ytterbium doping leads to high electrostatic properties, allowing for significant charge transfer from molecules to semiconductors.

Casein kinase 1α mediates estradiol secretion via CYP19A1 expression in mouse ovarian granulosa cells.

Background: Casein kinase 1α (CK1α), expressed in both ovarian germ and somatic cells, is involved in the initial meiosis and primordial follicle formation of mouse oocytes. Using in vitro and in vivo experiments in this study, we explored the function and mechanism of CK1α in estrogen synthesis in mice ovarian granulosa cells.

Methods: A CK1α knockout (cKO) mouse model, targeted specifically to ovarian granulosa cells (GCs), was employed to establish the influence of CK1α on in vivo estrogen synthesis.

Generation of a human SLC12A3 knock-in human induced pluripotent stem cell line (CMCi014-A-82) using CRISPR-Cas9 system.

Gitelman's disease is caused by a genetic mutation in the solute carrier family 12 member 3 (SLC12A3) gene, which encodes the sodium chloride cotransporter. In this study, we generated a stable human induced pluripotent stem cell (hiPSC) line, WTC11-SLC12A3 (CMCi014-A-82), by knocking in the entire SLC12A3 gene at the SHS231 locus in healthy wild-type control hiPSCs (WTC11). We verified that WTC11-SLC12A3 expressed pluripotency markers and exhibited normal stem cell morphology.

CRISPR/Cas9-mediated suppression of A4GALT rescues endothelial cell dysfunction in a fabry disease vasculopathy model derived from human induced pluripotent stem cells.

Background And Aims: The objective of this study was to investigate the efficacy of CRISPR/Cas9-mediated A4GALT suppression in rescuing endothelial dysfunction in Fabry disease (FD) endothelial cells (FD-ECs) derived from human induced pluripotent stem cells (hiPSCs).

Methods: We differentiated hiPSCs (WT (wild-type), WTC-11), GLA-mutant hiPSCs (GLA-KO, CMC-Fb-002), and CRISPR/Cas9-mediated A4GALT-KO hiPSCs (GLA/A4GALT-KO, Fb-002-A4GALT-KO) into ECs and compared FD phenotypes and endothelial dysfunction. We also analyzed the effect of A4GALT suppression on reactive oxygen species (ROS) formation and transcriptome profiles through RNA sequencing.

Generation of green fluorescent protein reporter knock-in iPSC line at the 3'UTR region of the KLOTHO locus.

We generated a human induced pluripotent stem cell (hiPSC) line (CMCi014-A-78) expressing a GFP reporter in the 3'-UTR region of the KLOTHO locus using CRISPR/Cas9-mediated homologous recombination to screen for candidates regulating KLOTHO. The established cell line exhibits a normal karyotype, typical stem cell morphology, expression of pluripotency markers, and the ability to differentiate into the three germ layers. Consequently, this hiPSC line could serve as a valuable resource for screening KLOTHO regulators in hiPSC-derived target cells or organoids.

Enhanced photocatalytic performance of NiFeO/ZnInS p-n heterojunction for efficient degradation of tetracycline.

The persistent release of tetracycline into the environment significantly endangers both ecosystems and human health. Zinc indium sulfide (ZnInS) capable to degrade tetracycline pollutants under visible light irradiation has attracted extensive attentions and great effort has been devoted to augment its catalytic efficacy. In this work, we synthesized a p-n heterojunction, NiFeO/ZnInS, to enhance the carrier migration rate and explained the intrinsic mechanism by density functional theory.

Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) Promotes the Adipogenesis of Intramuscular Preadipocytes through PI3K/AKT Pathway in Goats.

As a transcription factor, Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) binds to downstream target genes to participate in cell proliferation and cell differentiation. We found that the NR4A1 reached the highest expression at 60 h after the differentiation of goat intramuscular preadipocytes. Overexpression of goat NR4A1 increased the number of intracellular lipid droplets and up-regulated the expression of adipocyte-differentiation-related marker genes including , , , , and , while the relative expression levels of and were significantly decreased.

Advancements in Research on Genetic Kidney Diseases Using Human-Induced Pluripotent Stem Cell-Derived Kidney Organoids.

Genetic or hereditary kidney disease stands as a pivotal cause of chronic kidney disease (CKD). The proliferation and widespread utilization of DNA testing in clinical settings have notably eased the diagnosis of genetic kidney diseases, which were once elusive but are now increasingly identified in cases previously deemed CKD of unknown etiology. However, despite these diagnostic strides, research into disease pathogenesis and novel drug development faces significant hurdles, chiefly due to the dearth of appropriate animal models and the challenges posed by limited patient cohorts in clinical studies.

Single-cell RNA sequencing revealed the role of the Th17 pathway in the development of anti- human leukocyte antigen antibodies in a highly sensitized mouse model.

Background: The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse.

Methods: For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.