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Stress and risk of breast cancer; findings from a large population-based incident case-control study
Leptin-induced autophagy regulates the immunomodulatory potential of adipose-derived mesenchymal stem cells through down regulating the expression of TSG-6
Abstract Adipose-derived mesenchymal stem cells (ADMSCs) possess modulatory functions in adipose tissue, which could help combat the development of obesity. It has been reported that the functions of ADMSCs are impaired by obese microenvironment. However, the mechanisms are not clearly understood. The study investigates the role of leptin on immunoinhibitory functions of ADMSCs in obesity, and primarily explored its possible mechanisms. ADMSCs were isolated and identified by morphological observation, flow cytometry and differentiation potential. The lipopolysaccharides (LPS)-stimulated macrophages were co-cultured with ADMSCs pretreated with or without leptin. The expression of macrophage-associated markers was detected by flow cytometry. The secretion of inflammatory cytokines was evaluated by ELISA. Autophagy and MAPK signaling related proteins were detected by western blotting. Furthermore, the expression of tumor necrosis factor-alpha-stimulated protein 6 (TSG-6) was detected by western blotting, qRT-PCR, and ELISA. ADMSCs belonged to CD73 + CD90 + CD105 + / CD14 - CD34 - CD45 - HLA-DR - cells, and capable differentiation to adipogenic, osteogenic and chondrogenic cells. The immunosuppressive effect of ADMSCs on macrophage activation were restrained by leptin mediated the expression of TSG-6. Inhibition of leptin induced autophagy by Atg5 knockdown increased the expression of TSG-6, and promoted ADMSCs immunosuppression for macrophage activation. Furthermore, leptin induced autophagy and decreased the expression of TSG-6 in ADMSCs was dependent on the activation of p38 MAPK pathway. In conclusion, our study confirmed that leptin-induced autophagy regulated the immunomodulatory potential of ADMSCs through downregulating the expression of TSG-6 via the activation of p38 pathway. These findings reveal a novel mechanism and provide a potential molecular target for understanding the immunomodulatory dysfunction of ADMSCs in obesity.
Electron‐Induced C─F Bond Activation in Sn <sub>6</sub> ‐oxo Cluster Resist for Enhanced Sensitivity and Sub‐10‐nm Patterning
ABSTRACT Metal‐oxo cluster (MOC) resists are promising candidates for extreme ultraviolet lithography (EUVL), but optimizing the resolution, line‐edge roughness (LER), and sensitivity (RLS) trade‐off remains challenging. Leveraging dissociative electron attachment (DEA) to activate C─F bonds provides a controllable handle to improve this RLS trade‐off, yet remains underexplored. Here, we report a room‐temperature, scalable synthesis of a tunable series of Sn‐oxo clusters and demonstrate hundred‐gram‐scale, single‐batch production. The fluorinated FPAA demonstrates enhanced sensitivity without compromising resolution or LER. Under electron beam lithography (EBL), FPAA achieves a critical dimension (CD) of 9.1 nm and an LER of 2.2 nm, and enables high‐fidelity complex patterning. Additionally, FPAA exhibits robust performance under deep ultraviolet (DUV) lithography and EUVL, achieving a CD of 20.9 nm under EUVL. FPAA also shows exceptional plasma resistance, achieving a high estimated Si:resist etch selectivity of >50:1. Mechanistic analyses indicate that irradiation‐generated low‐energy secondary electrons (LESEs) promote electron‐induced C─F activation, consistent with a DEA‐mediated pathway. Concurrently, organic ligand bridging and Sn─O─Sn network densification occur, forming a crosslinked network that drives the solubility switch. This work elucidates the lithographic mechanisms of Sn‐oxo clusters and provides design principles for MOC resists, supporting progress toward sub‐10‐nm lithographic resolution.
Artificial Intelligence based on behavioral recognition and optimization for low carbon fertilization in agriculture
Cell polarity control by an unconventional G-protein complex in bacteria
Dose- and state-dependent enhancement of hippocampal CA1 pyramidal neuron excitability by GM1 ganglioside in male rats with cholinergic lesions
Abstract Cholinergic degeneration contributes to hippocampal circuit dysfunction in Alzheimer’s disease (AD). Ganglioside GM1 modulates membrane signaling and synaptic function, yet its acute effects on hippocampal neuronal activity under cholinergic-deficient conditions remain unclear. Using in vivo single-unit recordings in urethane-anesthetized male rats, extracellular single-unit activity was recorded from CA1 pyramidal neurons before and after systemic GM1 administration. We examined whether systemic GM1 alters spontaneous firing of CA1 pyramidal neurons in a nucleus basalis magnocellularis (NBM) lesion model of cholinergic hypofunction. GM1 (2, 5, 10 mg/kg, i.p.) produced dose-dependent increases in firing rate. Linear mixed-effects modeling, accounting for multiple neurons per animal, revealed a significant main effect of Time (F 1,79 = 41.33, p < 0.001, partial η 2 = 0.34) and a significant Dose × Time interaction (F 3,79 = 3.28, p = 0.025, partial η 2 = 0.11). Notably, NBM-lesioned animals exhibited amplified responses, particularly at 2 mg/kg (Δ = 7.22 ± 1.82 Hz), whereas control animals showed minimal change at this dose. GM1-induced increases remained within reported physiological firing ranges under urethane anesthesia. These findings demonstrate that GM1 enhances hippocampal CA1 excitability in a dose- and state-dependent manner, with heightened responsiveness in cholinergic-compromised networks. The results support the concept that membrane-targeting interventions may modulate dysfunctional circuits depending on baseline network state.
Single Ce atom-assisted oxygen vacancies as active and stable sites for CO2 conversion
Phosphoryl‐Engineered MOFs Promote Interfacial Reconstruction for Efficient Seawater Ethanol Electrooxidation
ABSTRACT The hydrogen production efficiency of hybrid seawater electrolysis devices hinges on high‐performance catalytic materials with superior activity and chlorine corrosion resistance under the alkaline seawater conditions. However, the controllable modulation of catalyst structures to construct an effective anti‐chlorine protective layer, one that simultaneously enhances both Cl corrosion resistance and anodic oxidation reaction activity, remains a formidable challenge. Herein, we report a phosphonyl‐ligand engineering strategy that promotes the transformation of metal–organic frameworks (MOFs) into metal oxyhydroxides containing oxygen‐anions during alkaline seawater ethanol oxidation reaction (EOR) with enhanced activity and Cl – corrosion resistance. Leveraging the tunable nature of organic ligands in MOFs provides a versatile platform for the in situ formation of oxygen anion layers with robust chlorine corrosion resistance. A phosphorus‐containing MOF (P a ‐Ni‐TPA) was synthesized by partially substituting terephthalic acid (TPA) with 4‐phosphonobenzoic acid (P a ). In contrast to the conventional MOF (Ni‐TPA), the in situ generated metal oxyhydroxide from P a ‐Ni‐TPA incorporates PO 4 3– . PO 4 3– promotes the adsorption of ethanol and its intermediates onto nickel centers while inhibiting Cl adsorption, thereby significantly boosting both EOR activity and Cl corrosion resistance. These findings establish a detailed structure‐performance correlation between MOF structural evolution and both catalytic activity toward alkaline seawater EOR and resistance to chlorine corrosion.
Livestock guardian dogs create safer landscapes for sheep by reducing fox predation risk attributes
Carbocycle editing of ketones proceeds via a radical-mediated bidirectional C-C bond cleavage/coupling strategy
Abstract 1,n-Difunctionalized alkyl linchpins are pivotal building blocks in organic synthesis, functional materials, and pharmaceuticals. However, their preparation currently relies predominantly on de novo synthesis, which is hampered by low step-economy and poor functional group compatibility. Herein, we report an efficient method based on a radical-mediated bidirectional C-C bond cleavage, which enables simple cyclic ketones to function as potential diradical linchpins via the formation of gem -diperoxides. It employs a stepwise and controllable tandem process involving alkoxy radical-induced β -scission and acyloxy radical-mediated decarboxylation, to achieve ring-opening, carbon shrinkage, and bidirectional functionalization of carbocycles. This carbocycle editing protocol features sustainable metal catalysis, a broad substrate scope, and excellent functional group compatibility. Notably, the cascade reaction enables facile and selective editing of various complex natural products and drug molecules. This bidirectional C-C bond cleavage/coupling strategy allows for rapid and modular synthesis of structurally diverse alkyl 1,n-dithiocyanides, 1,n-diazides, 1,n-dihalides, and unsymmetric 1,n-thiocyanate-azides ( n ≥ 4).
Coordination‐Driven Direct C─H Metalation of <i>N</i> ‐Heterocycles With a Superbasic Co(II) Amide Co(TMP) <sub>2</sub>
ABSTRACT Metalation of N ‐heterocycles such as pyridines or diazines with conventional alkali metal bases is particularly challenging due to the limited activation of their C─H bonds coupled with the thermal fragility of the resulting organometallic intermediates. Building upon previous work in this area, we demonstrate that the superbasic cobalt(II) amide Co(TMP) 2 (TMP = 2,2,6,6‐tetramethylpiperidide) enables high‐yielding and highly regioselective C─H metalation of a broad range of N ‐heterocycles via direct, redox‐neutral Co(II)–H exchange. This reactivity extends beyond single‐site activation, with controlled di‐cobaltation of non‐activated substrates such as pyrimidine and pyrazine. Via a combination of NMR reaction monitoring, isolation and characterisation of key organometallic intermediates, and density functional theory calculations, we establish that regioselectivity is dictated by coordination effects at positions α to nitrogen, overriding conventional trends based solely on C─H acidity. Exploiting cobalt's redox flexibility, oxidative treatment of the metalated intermediates with iodine enables selective C─N bond formation, giving sterically demanding TMP‐substituted heterocycles. Collectively, these findings establish Co(TMP) 2 as a mechanistically distinct and versatile reagent for the selective functionalisation of N ‐heterocycles.
Meaningful ciphertext encryption for color image via 2D-CICCM and stairwise compression
Engineering Crystalline Frameworks into Porous Liquids to Fabricate Graphene Oxide/Porous Liquid Membranes for Efficient Li+/Mg2+ Separation
Diastereodivergent Hydroamidation of Methylenecyclohexanes With Differentiated Active Catalytic Species
ABSTRACT The construction of three‐dimensional (3D) organic molecular structures is pivotal in modern organic chemistry. For three dimensionally structured disubstituted cyclohexanes, which exist as two possible configurations ( cis ‐ and trans ‐), substituent orientation dictates thermodynamic stability, physicochemical properties, and biological activities, but precise stereocontrol of cycloalkane substituents is challenging. Herein, we report the diastereodivergent hydroamidation of methylenecyclohexanes: a nickel catalytic system efficiently synthesizes 1,4‐ cis / trans and 1,3‐ cis / trans isomers, while a cobalt system realizes 1,2‐ cis / trans stereodivergence. The core achievement lies in a strategy utilizing differentiated active catalytic species, which enables the precise regulation of the spatial structure and electronic properties of metal‐hydride or metal‐functional group intermediates. This work broadens the chemical space for multi‐substituted cyclohexane synthesis, provides a powerful tool for the preparation of cycloalkyl‐containing drug molecules, and offers an important case for research on substituted cyclohexane stereochemistry.
Robust artificial intelligence frameworks for lung cancer subtyping and malignancy detection on thoracic CT
An invariant VLR-like receptor refines the T-like cell framework in lamprey
Qing Tang
Fused‐Ring Acceptor–π–Acceptor Architecture Enables Near‐Infrared‐Absorbing Mesoporous Covalent Organic Frameworks for Enhanced H <sub>2</sub> O <sub>2</sub> Photosynthesis
ABSTRACT Covalent organic frameworks (COFs) featuring donor–acceptor architectures have shown great promise as photocatalysts. However, their performance is often hindered by limitations such as narrow absorbance ranges and restricted electron delocalization, which are inherent to traditional imine linkages. Herein, we introduce a fused‐ring acceptor–π–acceptor (FRA–π–A) architecture for near‐infrared‐absorbing COFs, enabled via in situ COF‐to‐COF transformation that replaces imine linkages with FRA‐derived benzodithiazoles (or benzodioxazoles). Comprehensive structural characterizations confirm their mesoporous crystalline structure, featuring pore size distribution of 2.16–2.39 nm and broad light absorption extending to near‐infrared region. Property investigations demonstrate that the rigid backbones derived from the FRA–π–A architecture significantly enhance long‐range in‐plane electron delocalization, thereby improving the separation and transport of photogenerated charge carriers. Crucially, the accelerated carrier migration preferentially directs photogenerated electrons to the FRAs, promoting the formation of •O 2 − radicals and accelerating the rate‐limiting step of the oxygen reduction reaction. These synergistic structural and optoelectronic properties endow the FRA–π–A COFs with an outstanding photocatalytic H 2 O 2 production rate of 6.8 mmol g − 1 h − 1 without sacrificial agents, exceeding the vast majority of conjugated linkage‐based COFs. This study highlights the immense potential of FRA–π–A COFs as high‐performance photocatalysts.