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1.
Adv Mater ; : e2408094, 2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39096074

ABSTRACT

Multinuclear metal clusters are ideal candidates to catalyze small molecule activation reactions involving the transfer of multiple electrons. However, synthesizing active metal clusters is a big challenge. Herein, on constructing an unparalleled Co4(SO4)4 cluster within porphyrin-based metal-organic frameworks (MOFs) and the electrocatalytic features of such Co4(SO4)4 clusters for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is reported. The reaction of CoII sulfate and metal complexes of tetrakis(4-pyridyl)porphyrin under solvothermal conditions afforded Co4-M-MOFs (M═Co, Cu, and Zn). Crystallographic studies revealed that these Co4-M-MOFs have the same framework structure, having the Co4(SO4)4 clusters connected by metalloporphyrin units through Co─Npyridyl bonds. In the Co4(SO4)4 cluster, the four CoII ions are chemically and symmetrically equivalent and are each coordinated with four sulfate O atoms to give a distorted cube-like structure. Electrocatalytic studies showed that these Co4-M-MOFs are all active for electrocatalytic OER and ORR. Importantly, by regulating the activity of the metalloporphyrin units, it is confirmed that the Co4(SO4)4 cluster is active for oxygen electrocatalysis. With the use of Co porphyrins as connecting units, Co4-Co-MOF displays the highest electrocatalytic activity in this series of MOFs by showing a 10 mA cm-2 OER current density at 357 mV overpotential and an ORR half-wave potential at 0.83 V versus reversible hydrogen electrode (RHE). Theoretical studies revealed the synergistic effect of two proximal Co atoms in the Co4(SO4)4 cluster in OER by facilitating the formation of O─O bonds. This work is of fundamental significance to present the construction of Co4(SO4)4 clusters in framework structures for oxygen electrocatalysis and to demonstrate the cooperation between two proximal Co atoms in such clusters during the O─O bond formation process.

2.
Microbiol Res ; 287: 127836, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39018831

ABSTRACT

Verticillium dahliae is a destructive, soil-borne pathogen that causes significant losses on numerous important dicots. Recently, beneficial microbes inhabiting the rhizosphere have been exploited and used to control plant diseases. In the present study, Burkholderia gladioli KRS027 demonstrated excellent inhibitory effects against Verticillium wilt in cotton seedlings. Plant growth and development was promoted by affecting the biosynthesis and signaling pathways of brassinosteroids (BRs), gibberellins (GAs), and auxins, consequently promoting stem elongation, shoot apical meristem, and root apical tissue division in cotton. Furthermore, based on the host transcriptional response to V. dahliae infection, it was found that KRS027 modulates the plants to maintain cell homeostasis and respond to other pathogen stress. Moreover, KRS027 induced disruption of V. dahliae cellular structures, as evidenced by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. Based on the comparative transcriptomic analysis between KRS027 treated and control group of V. dahliae, KRS027 induced substantial alterations in the transcriptome, particularly affecting genes encoding secreted proteins, small cysteine-rich proteins (SCRPs), and protein kinases. In addition, KRS027 suppressed the growth of different clonal lineages of V. dahliae strains through metabolites, and volatile organic compounds (VOCs) released by KRS027 inhibited melanin biosynthesis and microsclerotia development. These findings provide valuable insights into an alternative biocontrol strategy for Verticillium wilt, demonstrating that the antagonistic bacterium KRS027 holds promise as a biocontrol agent for promoting plant growth and managing disease occurrence.


Subject(s)
Ascomycota , Burkholderia gladioli , Plant Diseases , Transcriptome , Plant Diseases/microbiology , Plant Diseases/prevention & control , Burkholderia gladioli/growth & development , Burkholderia gladioli/genetics , Burkholderia gladioli/metabolism , Ascomycota/growth & development , Ascomycota/genetics , Gossypium/microbiology , Gossypium/growth & development , Plant Development , Plant Growth Regulators/metabolism , Seedlings/microbiology , Seedlings/growth & development , Gene Expression Profiling , Host-Pathogen Interactions , Biological Control Agents , Indoleacetic Acids/metabolism , Gibberellins/metabolism , Verticillium
3.
Environ Int ; 189: 108811, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38870579

ABSTRACT

BACKGROUND: China produces and consumes a large amount of neonicotinoids. A non-negligible exposure to neonicotinoids might occur for Chinese pregnant women, but relevant data remain limited. OBJECTIVE: To investigate the exposure to neonicotinoids by urinary biomonitoring in pregnant women from Wenzhou City, East China. METHODS: We selected 432 pregnant women in Wenzhou City in 2022. A total of eight parent neonicotinoids and four metabolites were determined in single spot urine by liquid chromatography coupled to mass spectrometry. Basic characteristics, physical activity, pre-pregnant body mass index, and intake of drinking water and food were investigated by the questionnaire. Health risk was assessed by hazard quotient (HQ) and hazard index (HI) based on human safety thresholds derived from different health endpoints. RESULTS: Neonicotinoids and their metabolites in urine had a detection frequency between 0 % and 80.1 %. At least one neonicotinoid or metabolite was detected in 93.5 % of urine samples. Except for clothianidin (51.2 %) and N-desmethyl-acetamiprid (80.1 %), the detection frequencies of other neonicotinoids and metabolites ranged from 0 % to 43.8 %. The summed concentrations of all neonicotinoids and their metabolites ranged from < LOD to 222.83 µg/g creatinine with the median concentration of 2.58 µg/g creatinine. Maternal age, educational level, occupation, household income, screen time, and pre-pregnant body mass index were associated with detection frequencies or concentrations of neonicotinoids and their metabolites. Pregnant women with higher consumption frequencies of wheat, fresh vegetable, shellfish, fresh milk, and powdered milk had higher detection frequencies of neonicotinoids and their metabolites. Both HQ and HI were less than one. CONCLUSIONS: Overall, pregnant women in Wenzhou City showed a notable frequency of exposure to at least one neonicotinoid, although the exposure frequency for each specific neonicotinoid was generally low. Several food items derived from plants and animals were potential exposure sources. A low health risk was found based on current safety thresholds.


Subject(s)
Biological Monitoring , Neonicotinoids , Humans , Female , China , Pregnancy , Neonicotinoids/urine , Neonicotinoids/analysis , Adult , Young Adult , Insecticides/urine , Insecticides/analysis , Environmental Exposure/statistics & numerical data , Environmental Exposure/analysis , Cities
4.
Adv Sci (Weinh) ; : e2401137, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38868913

ABSTRACT

Due to its decade-long progression, colorectal cancer (CRC) is most suitable for population screening to achieve a significant reduction in its incidence and mortality. DNA methylation has emerged as a potential marker for the early detection of CRC. However, the current mainstream methylation detection method represented by bisulfite conversion has issues such as tedious operation, DNA damage, and unsatisfactory sensitivity. Herein, a new high-performance CRC screening tool based on the promising specific terminal-mediated polymerase chain reaction (STEM-PCR) strategy is developed. CRC-related methylation-specific candidate CpG sites are first prescreened through The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases using self-developed bioinformatics. Next, 9 homebrew colorectal cancer DNA methylated STEM‒PCR assays (ColoC-mSTEM) with high sensitivity (0.1%) and high specificity are established to identify candidate sites. The clinical diagnostic performance of these selected methylation sites is confirmed and validated by a case-control study. The optimized diagnostic model has an overall sensitivity of 94.8% and a specificity of 95.0% for detecting early-stage CRC. Taken together, ColoC-mSTEM, based on a single methylation-specific site, is a promising diagnostic approach for the early detection of CRC which is perfectly suitable for the screening needs of CRC in primary healthcare institutions.

5.
J Am Chem Soc ; 146(23): 15887-15896, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38825776

ABSTRACT

Oxide thin films grown on metal surfaces have wide applications in catalysis and beyond owing to their unique surface structures compared to their bulk counterparts. Despite extensive studies, the atomic structures of copper surface oxides on Cu(111), commonly referred to as "44" and "29", have remained elusive. In this work, we demonstrated an approach for the structural determination of oxide surfaces using element-specific scanning tunneling microscopy (STM) imaging enhanced by functionalized tips. This approach enabled us to resolve the atomic structures of "44" and "29" surface oxides, which were further corroborated by noncontact atomic force microscopy (nc-AFM) measurements and Monte Carlo (MC) simulations. The stoichiometry of the "44" and "29" frameworks was identified as Cu23O16 and Cu16O11, respectively. Contrary to the conventional hypothesis, we observed ordered Cu vacancies within the "44" structure manifesting as peanut-shaped cavities in the hexagonal lattice. Similarly, a combination of Cu and O vacancies within the "29" structure leads to bean-shaped cavities within the pentagonal lattice. Our study has thus resolved the decades-long controversy on the atomic structures of "44" and "29" surface oxides, advancing our understanding of copper oxidation processes and introducing a robust framework for the analysis of complex oxide surfaces.

6.
Angew Chem Int Ed Engl ; 63(36): e202409793, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-38923266

ABSTRACT

Due to the challenge of cleaving O-O bonds at single Co sites, mononuclear Co complexes typically show poor selectivity for the four-electron (4e-) oxygen reduction reaction (ORR). Herein, we report on selective 4e- ORR catalyzed by a Co porphyrin with a hanged ZnII ion. Inspired by Cu/Zn-superoxide dismutase, we designed and synthesized 1-CoZn with a hanging ZnII at the second sphere of a Co porphyrin. Complex 1-CoZn is much more effective than its Zn-lacking analogues to catalyze the 4e- ORR in neutral aqueous solutions, giving an electron number of 3.91 per O2 reduction. With spectroscopic studies, the hanging ZnII was demonstrated to be able to facilitate the electron transfer from CoII to O2, through an electronic "pull effect", to give CoIII-superoxo. Theoretical studies further suggested that this "pull effect" plays crucial roles in assisting O-O bond cleavage. This work is significant to present a new strategy of hanging a ZnII to improve O2 activation and O-O bond cleavage.

7.
ACS Appl Mater Interfaces ; 16(15): 19379-19390, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38568698

ABSTRACT

Photodriven chiral catalysis is the combination of photocatalysis and chiral catalysis and is considered one of the cleanest and most efficient methods for the synthesis of chiral compounds or drugs. Furthermore, due to the potential metal contamination associated with most metal-based catalysts, metal-free chiral photocatalysts are ideal candidates. In this work, we demonstrate that metal-free chiral carbon dots (CDs) exhibit size-dependent enantioselective photocatalytic activity. Using serine as the raw material, chiral CDs with well-defined structures and average sizes of 2.22, 3.01, 3.70, 4.77, and 7.21 nm were synthesized using the electrochemical method. These chiral CDs possess size-dependent band gaps and exhibit photoresponsive enantioselective catalytic activity toward the oxidation of dihydroxyphenylalanine (DOPA). Under light-assisted conditions, chiral CDs (L72, 500 µg/mL) exhibit high selectivity (selectivity factor: 2.07) and maintain a certain level of catalytic activity (1.34 µM/min) even at a low temperature of 5 °C. The high catalytic activity of the chiral CDs arises from their photoelectrons reducing O2 to generate O2-, as the active oxygen species for DOPA oxidation. The high enantioselectivity of the chiral CDs is attributed to their differential adsorption capabilities toward DOPA enantiomers. This study provides a new approach for designing metal-free chiral photocatalysts with high enantioselectivity.

8.
Nat Commun ; 15(1): 3030, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589464

ABSTRACT

On-surface synthesis provides tools to prepare low-dimensional supramolecular structures. Traditionally, reactive radicals are a class of single-electron species, serving as exceptional electron-withdrawing groups. On metal surfaces, however, such species are affected by conduction band screening effects that may even quench their unpaired electron characteristics. As a result, radicals are expected to be less active, and reactions catalyzed by surface-stabilized radicals are rarely reported. Herein, we describe a class of inter-molecular radical transfer reactions on metal surfaces. With the assistance of aryl halide precursors, the coupling of terminal alkynes is steered from non-dehydrogenated to dehydrogenated products, resulting in alkynyl-Ag-alkynyl bonds. Dehalogenated molecules are fully passivated by detached hydrogen atoms. The reaction mechanism is unraveled by various surface-sensitive technologies and density functional theory calculations. Moreover, we reveal the universality of this mechanism on metal surfaces. Our studies enrich the on-surface synthesis toolbox and develop a pathway for producing low-dimensional organic materials.

9.
Pharmacol Res ; 203: 107172, 2024 May.
Article in English | MEDLINE | ID: mdl-38583685

ABSTRACT

Although anti-TNF antibodies are extensively used to treat Crohn's disease (CD), a significant proportion of patients, up to 40%, exhibit an inadequate response to this therapy. Our objective was to identify potential targets that could improve the effectiveness of anti-TNF therapy in CD. Through the integration and analysis of transcriptomic data from various CD databases, we found that the expression of AQP9 was significantly increased in anti-TNF therapy-resistant specimens. The response to anti-TNF therapy in the CD mouse model was significantly enhanced by specifically inhibiting AQP9. Further experiments found that the blockade of AQP9, which is dominantly expressed in macrophages, decreased inflamed macrophage functions and cytokine expression. Mechanistic studies revealed that AQP9 transported glycerol into macrophages, where it was metabolized to LPA, which was further metabolized to LPA, resulting in the activation of the LPAR2 receptor and downstream hippo pathway, finally promoting the expression of cytokines, especially IL23 and IL1ß⊡ Taken together, the expansion of AQP9+ macrophages is associated with resistance to anti-TNF therapy in Crohn's disease. These findings indicated that AQP9 could be a potential target for enhancing anti-TNF therapy in Crohn's disease.


Subject(s)
Aquaporins , Crohn Disease , Hippo Signaling Pathway , Lysophospholipids , Macrophages , Animals , Humans , Male , Mice , Aquaporins/metabolism , Aquaporins/genetics , Aquaporins/antagonists & inhibitors , Crohn Disease/drug therapy , Crohn Disease/metabolism , Cytokines/metabolism , Hippo Signaling Pathway/drug effects , Lysophospholipids/metabolism , Macrophages/metabolism , Macrophages/drug effects , Mice, Inbred C57BL , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Receptors, Lysophosphatidic Acid/antagonists & inhibitors , Receptors, Lysophosphatidic Acid/metabolism , Signal Transduction/drug effects , Tumor Necrosis Factor Inhibitors/therapeutic use , Tumor Necrosis Factor Inhibitors/pharmacology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/metabolism
10.
J Immunother Cancer ; 12(3)2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38458635

ABSTRACT

BACKGROUND: Programmed death 1 (PD-1) inhibitor demonstrated durable antitumor activity in advanced esophageal squamous cell carcinoma (ESCC), but the clinical benefit of perioperative immunotherapy in ESCC remains unclear. This study evaluated the efficacy and safety of neoadjuvant chemoradiotherapy (nCRT) combined with the PD-1 inhibitor toripalimab in patients with resectable ESCC. METHODS: From July 2020 to July 2022, 21 patients with histopathologically confirmed thoracic ESCC and clinical staged as cT1-4aN1-2M0/cT3-4aN0M0 were enrolled. Eligible patients received radiotherapy (23 fractions of 1.8 Gy, 5 fractions a week) with concurrent chemotherapy of paclitaxel/cisplatin (paclitaxel 45 mg/m2 and cisplatin 25 mg/m2) on days 1, 8, 15, 22, 29 and two cycles of toripalimab 240 mg every 3 weeks after nCRT for neoadjuvant therapy before surgery, four cycles of toripalimab 240 mg every 3 weeks for adjuvant therapy after surgery. The primary endpoint was the major pathological response (MPR) rate. The secondary endpoints were safety and survival outcomes. RESULTS: A total of 21 patients were included, of whom 20 patients underwent surgery, 1 patient refused surgery and another patient was confirmed adenocarcinoma after surgery. The MPR and pathological complete response (pCR) rates were 78.9% (15/19) and 47.4% (9/19) for surgery ESCC patients. 21 patients (100.0%) had any-grade treatment-related adverse events, with the most common being lymphopenia (100.0%), leukopenia (85.7%), neutropenia (52.4%). 14 patients (66.7%) had adverse events of grade 3 with the most common being lymphopenia (66.7%). The maximum standardized uptake value and total lesion glycolysis of positron emission tomography/CT after neoadjuvant therapy well predicted the pathological response. The peripheral CD4+%, CD3+HLA-DR+/CD3+%, CD8+HLA-DR+/CD8+%, and IL-6 were significant differences between pCR and non-pCR groups at different times during neoadjuvant therapy. Three patients had tumor relapse and patients with MPR have longer disease-free survival than non-MPR patients. CONCLUSIONS: nCRT combined with perioperative toripalimab is effective and safe for locally advanced resectable ESCC. Long-term survival outcomes remain to be determined. TRIAL REGISTRATION NUMBER: NCT04437212.


Subject(s)
Antibodies, Monoclonal, Humanized , Carcinoma, Squamous Cell , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Lymphopenia , Thrombocytopenia , Humans , Esophageal Squamous Cell Carcinoma/drug therapy , Esophageal Squamous Cell Carcinoma/pathology , Cisplatin/therapeutic use , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/pathology , Neoadjuvant Therapy , Carcinoma, Squamous Cell/drug therapy , Treatment Outcome , Neoplasm Recurrence, Local , Paclitaxel , HLA-DR Antigens , Epithelial Cells/pathology
11.
Cell Oncol (Dordr) ; 47(4): 1149-1165, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38386232

ABSTRACT

PURPOSE: Growth differentiating Factor 15 (GDF15) is linked to several cancers, but its effect on chemoresistance in colorectal cancer (CRC) remains unclear. Here, we investigated the role of GDF15 in the chemotherapeutic response of CRC patients to oxaliplatin (L-OHP). METHODS: GDF15 levels in serum and tumour tissues were detected in CRC patients have received L-OHP-based neoadjuvant chemotherapy. The effects of GDF15 neutralization or GDF15 knockdown on cell proliferation, apoptosis and intracellular reactive oxygen species (ROS) levels were analysed in vitro and in vivo. Co-immunoprecipitation (Co-IP), Chromatin Immunoprecipitation (ChIP) and luciferase reporter assays were used to explore the interaction between GDF15 and Nrf2. RESULTS: In this study, we found that GDF15 alleviates oxidative stress to induce chemoresistance of L-OHP in CRC. Mechanically, GDF15 posttranscriptionally regulates protein stability of Nrf2 through the canonical PI3K/AKT/GSK3ß signaling pathway, and in turn, Nrf2 acts as a transcription factor to regulate GDF15 expression to form a positive feedback loop, resulting in the maintenance of redox homeostasis balance in CRC. Furthermore, a positive correlation between GDF15 and Nrf2 was observed in clinical CRC samples, and simultaneous overexpression of both GDF15 and Nrf2 was associated with poor prognosis in CRC patients treated with L-OHP. Simultaneous inhibition of both GDF15 and Nrf2 significantly increases the response to L-OHP in an L-OHP-resistant colorectal cancer cells-derived mouse xenograft model. CONCLUSION: This study identified a novel GDF15-Nrf2 positive feedback loop that drives L-OHP resistance and suggested that the GDF15-Nrf2 axis is a potential therapeutic target for the treatment of L-OHP-resistant CRC.


Subject(s)
Colorectal Neoplasms , Drug Resistance, Neoplasm , Feedback, Physiological , Growth Differentiation Factor 15 , Homeostasis , NF-E2-Related Factor 2 , Oxaliplatin , Oxidation-Reduction , Growth Differentiation Factor 15/metabolism , Growth Differentiation Factor 15/genetics , Humans , Oxaliplatin/pharmacology , Oxaliplatin/therapeutic use , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Colorectal Neoplasms/genetics , Colorectal Neoplasms/drug therapy , NF-E2-Related Factor 2/metabolism , Drug Resistance, Neoplasm/drug effects , Drug Resistance, Neoplasm/genetics , Animals , Oxidation-Reduction/drug effects , Feedback, Physiological/drug effects , Cell Line, Tumor , Homeostasis/drug effects , Mice, Nude , Male , Mice , Female , Signal Transduction/drug effects , Cell Proliferation/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Middle Aged , Mice, Inbred BALB C , Reactive Oxygen Species/metabolism , Apoptosis/drug effects
12.
Angew Chem Int Ed Engl ; 63(7): e202313034, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38097503

ABSTRACT

Oxygen reduction reaction (ORR) is of critical significance in the advancement of fuel cells and zinc-air batteries. The iron-nitrogen (Fe-Nx ) sites exhibited exceptional reactivity towards ORR. However, the task of designing and controlling the local structure of Fe species for high ORR activity and stability remains a challenge. Herein, we have achieved successful immobilization of Fe species onto the highly curved surface of S, N co-doped carbonaceous nanosprings (denoted as FeNS/Fe3 C@CNS). The induction of this twisted configuration within FeNS/Fe3 C@CNS arose from the assembly of chiral templates. For electrocatalytic ORR tests, FeNS/Fe3 C@CNS exhibits a half-wave potential (E1/2 ) of 0.91 V in alkaline medium and a E1/2 of 0.78 V in acidic medium. The Fe single atoms and Fe3 C nanoparticles are coexistent and play as active centers within FeNS/Fe3 C@CNS. The highly curved surface, coupled with S substitution in the coordination layer, served to reduce the energy barrier for ORR, thereby enhancing the intrinsic catalytic activity of the Fe single-atom sites. We also assembled a wearable flexible Zn-air battery using FeNS/Fe3 C@CNS as electrocatalysts. This work provides new insights into the construction of highly curved surfaces within carbon materials, offering high electrocatalytic efficacy and remarkable performance for flexible energy conversion devices.

13.
J Phys Chem Lett ; 14(50): 11286-11291, 2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38063416

ABSTRACT

Thermal stimulus has been considered as a promising strategy for controlling on-surface reactions, allowing the formation of diverse products on metal substrates. Here, we successfully achieve hierarchical dehydrogenation reactions of amino groups on a Cu(100) surface. By carefully adjusting the experimental parameters, we synthesize large-scale and low-defect density surface metal-organic frameworks on copper surfaces. Our work sheds light on a controllable route for the synthesis of high-quality metal-organic coordination supramolecular structures via on-surface chemistry.

14.
ACS Nano ; 17(22): 22691-22700, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-37926947

ABSTRACT

High-entropy alloys (HEAs) are significantly promising candidates for heterogeneous catalysis, yet the controllable synthesis of ultrafine HEA nanoparticles (NPs) remains a formidable challenge due to severe thermal sintering during the high-temperature fabrication process. Herein, we report a sulfur-stabilizing strategy to construct ultrafine HEA NPs with an average diameter of 4.02 nm supported on sulfur-modified Ti3C2Tx (S-Ti3C2Tx) MXene, on which the strong interfacial metal-sulfur interactions between HEA NPs and the S-Ti3C2Tx supports significantly increase the interfacial adhesion strength, thus greatly suppressing nanoparticle sintering by retarding both particle migration and metal atom diffusion. The representative quinary PtPdCuNiCo HEA-S-Ti3C2Tx exhibits excellent catalytic performance toward alkaline ethanol oxidation reaction (EOR) with an ultrahigh mass activity of 7.03 A mgPt+Pd-1, which is 4.34 and 5.17 times higher than those of the commercial Pt/C and Pd/C catalysts, respectively. In situ attenuated total reflection-infrared spectroscopy studies reveal that the high intrinsic catalytic activity for the EOR can be ascribed to the synergy of different catalytically active sites of HEA NPs and the well-designed interfacial metal-sulfur interactions.

15.
J Phys Chem Lett ; 14(43): 9584-9589, 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-37862333

ABSTRACT

Two-dimensional (2D) tessellation of organic species acquired increased interest recently because of their potential applications in physics, biology, and chemistry. Herein, we successfully synthesized the chiral distorted Kagome lattice p3 (333) with bicomponent precursors on Ag(111). Scanning tunneling microscopy and density functional calculation studies reveal that the networks are formed by multiple intermolecular hydrogen bonds. The network structures can be rationally tuned by adjusting the stoichiometric ratio of the reaction precursors. Our study provides new strategies to synthesize complex low-dimensional nanostructures on metal surfaces.

16.
Adv Mater ; 35(42): e2305659, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37620729

ABSTRACT

Oxygen evolution reaction (OER) plays a key role in proton exchange membrane water electrolysis (PEMWE), yet the electrocatalysts still suffer from the disadvantages of low activity and poor stability in acidic conditions. Here, a new class of CdRu2 IrOx nanoframes with distorted structure for acidic OER is successfully fabricated. Impressively, CdRu2 IrOx displays an ultralow overpotential of 189 mV and an ultralong stability of 1500 h at 10 mA cm⁻2 toward OER in 0.5 M H2 SO4 . Moreover, a PEMWE using the distorted CdRu2 IrOx can be steadily operated at 0.1 A cm⁻2 for 90 h. Microstructural analyses and X-ray absorption spectroscopy (XAS) demonstrate that the synergy between Ru and Ir in CdRu2 IrOx induces the distortion of Ru-O, Ir-O, and Ru-M (M = Ru, Ir) bonds. In situ XAS indicates that the applied potential leads to the deformation octahedral structure of RuOx /IrOx and the formation of stable Ru5+ species for OER. Theoretical calculations also reveal that the distorted structures can reduce the energy barrier of rate-limiting step during OER. This work provides an efficient strategy for constructing structural distortion to achieve significant enhancement on the activity and stability of OER catalysts.

17.
Angew Chem Int Ed Engl ; 62(39): e202308670, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37551119

ABSTRACT

Electrochemical water splitting is a promising approach for producing sustainable and clean hydrogen. Typically, high valence state sites are favorable for oxidation evolution reaction (OER), while low valence states can facilitate hydrogen evolution reaction (HER). However, here we proposed a high valence state of Co3+ in Ni9.5 Co0.5 -S-FeOx hybrid as the favorable center for efficient and stable HER, while structural analogues with low chemical states showed much worse performance. As a result, the Ni9.5 Co0.5 -S-FeOx catalyst could drive alkaline HER with an ultra-low overpotential of 22 mV for 10 mA cm-2 , and 175 mV for 1000 mA cm-2 at the industrial temperature of 60 °C, with an excellent stability over 300 h. Moreover, this material could work for both OER and HER, with a low cell voltage being 1.730 V to achieve 1000 mA cm-2 for overall water splitting at 60 °C. X-ray absorption spectroscopy (XAS) clearly identified the high valence Co3+ sites, while in situ XAS during HER and theoretical calculations revealed the favorable electron capture at Co3+ and suitable H adsorption/desorption energy around Co3+ , which could accelerate the HER. The understanding of high valence states to drive reductive reactions may pave the way for the rational design of energy-related catalysts.

18.
Front Cell Infect Microbiol ; 13: 1140757, 2023.
Article in English | MEDLINE | ID: mdl-37124046

ABSTRACT

The fungal microbiota is an important component of the complex multikingdom microbial community colonizing the mammalian gastrointestinal tract and has an important role in immune regulation. However, how fungi regulate inflammatory bowel disease (IBD) is poorly understood. This study found that intestinal fungi regulate immune responses in IBD. Antibiotic-mediated depletion of fungi facilitated the development of IBD. Fungi greatly enhanced oxidative phosphorylation (OXPHOS) by enhancing glutaminolysis. Mechanistically, we found that fungi could activate the dectin-1-Syk- NF-κB signaling pathway to promote the expression of key enzymes and transporters involved in glutaminolysis. In summary, our findings reveal that fungal interactions in the human gut could be a promising therapeutic target for IBD.


Subject(s)
Dysbiosis , Gastrointestinal Microbiome , Inflammatory Bowel Diseases , Humans , CD4-Positive T-Lymphocytes , Dysbiosis/microbiology , Fungi , Inflammatory Bowel Diseases/microbiology , Mammals
19.
J Am Chem Soc ; 145(9): 5353-5362, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36853085

ABSTRACT

Photocatalysis provides an eco-friendly route for the hydrogenation of aromatic carbonyls to O-free aromatics, which is an important refining process in the chemical industry that is generally carried out under high pressure of hydrogen at elevated temperatures. However, aromatic carbonyls are often only partially hydrogenated to alcohols, which readily desorbs and are hardly further deoxygenated under ambient conditions. Here, we show that by constructing an oxide surface over the Pd cocatalyst supported on graphitic carbon nitride, an alternative hydrogenation path of aromatic carbonyls becomes available via a step-wise acetalization and hydrogenation, thus allowing efficient and selective production of O-free aromatics. The PdO surface allows for optimum adsorption of reactants and intermediates and rapid abstraction of hydrogen from the alcohol donor, favoring fast acetalization of the carbonyls and their consecutive hydrogenation to O-free hydrocarbons. The photocatalytic hydrogenation of benzaldehyde into toluene shows a high selectivity of >90% and a quantum efficiency of ∼10.2% under 410 nm irradiation. By adding trace amounts of HCl to the reaction solution, the PdO surface remains stable and active for long-term operation at high concentrations, offering perspective for practical applications.

20.
Clin Lung Cancer ; 24(3): e141-e151, 2023 05.
Article in English | MEDLINE | ID: mdl-36639280

ABSTRACT

BACKGROUND: The standard surgical procedure for ≤ 2 cm non-small cell lung cancer (NSCLC), including the number of lymph nodes sampled (nLN) and surgical modality, remains controversial. This study was designed to determine the optimal cohort in which sublobectomy could be an alternative to lobectomy. MATERIALS (OR PATIENTS) AND METHODS: Patients from 1998 to 2017 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The optimal cutoff value of nLN was identified using a restrictive cubic spline graph (RCS). Kaplan-Meier analysis was used to determine cancer-specific survival (CSS). The COX proportional hazard regression model was used to identify the influence of clinical and demographic variables on survival, and propensity score matching (PSM) was used to balance differences in baseline characteristics. Finally, we used an external cohort from a single-center medical institution to verify the conclusions drawn from the SEER database. RESULTS: A total of 6150 patients were included. The sublobectomy subgroup included segmentectomy (308, 5.0%) and wedge resection (1611, 26.2%). The cutoff value for nLN was 7. In the nLN ≥7 subgroup of the PSM cohort, the CSS of segmentectomy and wedge resection was close to that of the lobectomy subgroup (P = .12), whereas in the nLN <7 subgroup, the CSS of the lobectomy subgroup was significantly higher than that of the sublobectomy with P < .001). Surgical methods, nLN, age, sex, and differentiated grade were independent predictors of CSS. External cohort validation: A total of 1106 patients from the Affiliated Jinhua Hospital of Zhejiang University School of Medicine between 2013 and 2020 were included. The grouping criteria were consistent with the SEER database. In the nLN≥7 subgroup, sublobectomy had a survival outcome similar to that of lobectomy (P = .81). CONCLUSION: Sublobectomy and nLN < 7 were strongly associated with poorer CSS for early-stage NSCLC. On the premise of nLN ≥ 7, sublobectomy could provide similar survival outcomes to lobectomy for these patients.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Small Cell Lung Carcinoma , Humans , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Pneumonectomy/methods , Neoplasm Staging , Small Cell Lung Carcinoma/pathology , Lymph Nodes/surgery , Lymph Nodes/pathology
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