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1.
Nature ; 601(7892): 257-262, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937940

RESUMO

The methanogenic degradation of oil hydrocarbons can proceed through syntrophic partnerships of hydrocarbon-degrading bacteria and methanogenic archaea1-3. However, recent culture-independent studies have suggested that the archaeon 'Candidatus Methanoliparum' alone can combine the degradation of long-chain alkanes with methanogenesis4,5. Here we cultured Ca. Methanoliparum from a subsurface oil reservoir. Molecular analyses revealed that Ca. Methanoliparum contains and overexpresses genes encoding alkyl-coenzyme M reductases and methyl-coenzyme M reductases, the marker genes for archaeal multicarbon alkane and methane metabolism. Incubation experiments with different substrates and mass spectrometric detection of coenzyme-M-bound intermediates confirm that Ca. Methanoliparum thrives not only on a variety of long-chain alkanes, but also on n-alkylcyclohexanes and n-alkylbenzenes with long n-alkyl (C≥13) moieties. By contrast, short-chain alkanes (such as ethane to octane) or aromatics with short alkyl chains (C≤12) were not consumed. The wide distribution of Ca. Methanoliparum4-6 in oil-rich environments indicates that this alkylotrophic methanogen may have a crucial role in the transformation of hydrocarbons into methane.


Assuntos
Euryarchaeota , Hidrocarbonetos , Metano , Alcanos/metabolismo , Biodegradação Ambiental , Euryarchaeota/enzimologia , Euryarchaeota/genética , Hidrocarbonetos/metabolismo , Metano/metabolismo , Oxirredutases/metabolismo , Filogenia
2.
Proc Natl Acad Sci U S A ; 121(6): e2318341121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289957

RESUMO

As a prototypical photocatalyst, TiO[Formula: see text] has been extensively studied. An interesting yet puzzling experimental fact was that P25-a mixture of anatase and rutile TiO[Formula: see text]-outperforms the individual phases; the origin of this mysterious fact, however, remains elusive. Employing rigorous first-principles calculations, here we uncover a metastable intermediate structure (MIS), which is formed due to confinement at the anatase/rutile interface. The MIS has a high conduction-band minimum level and thus substantially enhances the overpotential of the hydrogen evolution reaction. Also, the corresponding band alignment at the interface leads to efficient separation of electrons and holes. The interfacial confinement additionally creates a wide distribution of the band gap in the vicinity of the interface, which in turn improves optical absorption. These factors all contribute to the enhanced photocatalytic efficiency in P25. Our insights provide a rationale to the puzzling superior photocatalytic performance of P25 and enable a strategy to achieve highly efficient photocatalysis via interface engineering.

3.
J Am Chem Soc ; 146(10): 6618-6627, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349322

RESUMO

Single-crystal semiconductor-based photocatalysts exposing unique crystallographic facets show promising applications in energy and environmental technologies; however, crystal facet engineering through solid-state synthesis for photocatalytic overall water splitting is still challenging. Herein, we develop a novel crystal facet engineering strategy through solid-state recrystallization to synthesize uniform SrTiO3 single crystals exposing tailored {111} facets. The presynthesized low-crystalline SrTiO3 precursors enable the formation of well-defined single crystals through kinetically improved crystal structure transformation during solid-state recrystallization process. By employing subtle Al3+ ions as surface morphology modulators, the crystal surface orientation can be precisely tuned to a controlled percentage of {111} facets. The photocatalytic overall water splitting activity increases with the exposure percentage of {111} facets. Owing to the outstanding crystallinity and favorable anisotropic surface structure, the SrTiO3 single crystals with 36.6% of {111} facets lead to a 3-fold enhancement of photocatalytic hydrogen evolution rates up to 1.55 mmol·h-1 in a stoichiometric ratio of 2:1 than thermodynamically stable SrTiO3 enclosed with isotropic {100} facets.

4.
Chem Biodivers ; 21(2): e202301781, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38146649

RESUMO

Polysaccharide from Asarum sieboldii Miq (ASP) was extracted and five phosphorylation polysaccharides with different degree of substitution were obtained, namely ASPP1, ASPP2, ASPP3, ASPP4, and ASPP5 (ASPPs). The physical and chemical structure and biological activities were studied. The results suggested that the carbohydrate and protein content were reduced while uronic acid was increased after phosphorylation modification. The molecular weight of ASPPs was significantly lower than that of ASP. ASPPs were acidic heteropolysaccharides mainly composed of galacturonic acid, galactose, glucose, fructose, and arabinose. The UV-vis spectrum indicated that the polysaccharides did not contain nucleic acid or protein after modification. The Fourier transform infrared spectrum demonstrated that ASPPs contained characteristic absorption peaks of P=O and P-O-C near 1270 and 980 cm-1 . ASPPs presented a triple helix conformation, but it was not presented in ASP. The scanning electron microscopy analysis showed that the surface topography and particle structure of ASP were different after modification. Compared with ASP, ASPPs enhanced the activity to scavenge DPPH and ABTS free radicals and possessed more protective ability to DNA oxidation caused by OH⋅, GS⋅, and AAPH free radicals. These results suggest that chemical modification is beneficial for the exploitation and utilization of natural polysaccharides.


Assuntos
Antioxidantes , Asarum , Antioxidantes/farmacologia , Antioxidantes/química , Fosforilação , Polissacarídeos/farmacologia , Polissacarídeos/química , Radicais Livres , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Angew Chem Int Ed Engl ; 63(25): e202404213, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38600431

RESUMO

Electrocatalytic carbon dioxide/carbon monoxide reduction reaction (CO(2)RR) has emerged as a prospective and appealing strategy to realize carbon neutrality for manufacturing sustainable chemical products. Developing highly active electrocatalysts and stable devices has been demonstrated as effective approach to enhance the conversion efficiency of CO(2)RR. In order to rationally design electrocatalysts and devices, a comprehensive understanding of the intrinsic structure evolution within catalysts and micro-environment change around electrode interface, particularly under operation conditions, is indispensable. Synchrotron radiation has been recognized as a versatile characterization platform, garnering widespread attention owing to its high brightness, elevated flux, excellent directivity, strong polarization and exceptional stability. This review systematically introduces the applications of synchrotron radiation technologies classified by radiation sources with varying wavelengths in CO(2)RR. By virtue of in situ/operando synchrotron radiationanalytical techniques, we also summarize relevant dynamic evolution processes from electronic structure, atomic configuration, molecular adsorption, crystal lattice and devices, spanning scales from the angstrom to the micrometer. The merits and limitations of diverse synchrotron characterization techniques are summarized, and their applicable scenarios in CO(2)RR are further presented. On the basis of the state-of-the-art fourth-generation synchrotron facilities, a perspective for further deeper understanding of the CO(2)RR process using synchrotron radiation analytical techniques is proposed.

6.
Angew Chem Int Ed Engl ; 63(15): e202319882, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38337137

RESUMO

Polar materials with spontaneous polarization (Ps) have emerged as highly promising photocatalysts for efficient photocatalytic H2 evolution owing to the Ps-enhanced photogenerated carrier separation. However, traditional inorganic polar materials often suffer from limitations such as wide band gaps and poor carrier transport, which hinders their photocatalytic H2 evolution efficiency. Here, we rationally synthesized a series of isostructural two-dimensional (2D) aromatic Dion-Jacobson (DJ) perovskites, namely (2-(2-Aminoethyl)pyridinium)PbI4 (2-APDPI), (3-(2-Aminoethyl)pyridinium)PbI4 (3-APDPI), and (4-(2-Aminoethyl)pyridinium)PbI4 (4-APDPI), where 2-APDPI and 4-APDPI crystalize in polar space groups with piezoelectric constants (d33) of approximately 40 pm V-1 and 3-APDPI adopts a centrosymmetric structure. Strikingly, owing to the Ps-facilitated separation of photogenerated carriers, polar 2-APDPI and 4-APDPI exhibit a 3.9- and 2.8-fold increase, respectively, in photocatalytic H2 evolution compared to the centrosymmetric 3-APDPI. As a pioneering study, this work provides an efficient approach for exploring new polar photocatalysts and highlights their potential in promoting photocatalytic H2 evolution.

7.
Small ; 19(23): e2207037, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36879480

RESUMO

Electrochemical CO2 -to-CO conversion offers an attractive and efficient route to recycle CO2 greenhouse gas. Molecular catalysts, like CoPc, are proved to be possible replacement for precious metal-based catalysts. These molecules, a combination of metal center and organic ligand molecule, may evolve into single atom structure for enhanced performance; besides, the manipulation of molecules' behavior also plays an important role in mechanism research. Here, in this work, the structure evolution of CoPc molecules is investigated via electrochemical-induced activation process. After numbers of cyclic voltammetry scanning, CoPc molecular crystals become cracked and crumbled, meanwhile the released CoPc molecules migrate to the conductive substrate. Atomic-scale HAADF-STEM proves the migration of CoPc molecules, which is the main reason for the enhancement in CO2 -to-CO performance. The as-activated CoPc exhibits a maximum FECO of 99% in an H-type cell and affords a long-term durability at 100 mA cm-2 for 29.3 h in a membrane electrode assembly reactor. Density-functional theory (DFT) calculation also demonstrates a favorable CO2 activation energy with such an activated CoPc structure. This work provides a different perspective for understanding molecular catalysts as well as a reliable and universal method for practical utilization.

8.
Chemistry ; 29(69): e202302055, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37720979

RESUMO

Designing highly excellent and stable catalysts for alkaline oxygen evolution reaction (OER) is gradually pivotal for clean energy development. In this work, a heterogeneous Fe-doped Ni(OH)2 (Ni/Fe-0.1) was developed via simple one-step electrodeposition onto nickel mesh. The heterogeneous interface structure generates sufficient active sites, significantly improving OER performance with an overpotential of 174 mV at 10 mA cm-2 (η10 ), while Tafel slope is only 43.0 mV dec-1 . In particular, Ni/Fe-0.1 is still able to operate stably at a current density of 1 A cm-2 for 100 h without obvious potential decay. The oxidation of Ni2+ to Ni3+ was detected by X-ray photoelectron spectroscopy, proving that the heterogeneous catalyst could stabilize the high-valence state of nickel as active sites to its superior OER performance. This work provides a convenient synthetic strategy for forming heterogeneous catalysts toward efficient water electrolysis.

9.
Chemistry ; 29(15): e202203165, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36514875

RESUMO

To simultaneously improve the hole extraction ability of the BiVO4 photoanode and accelerate the surface reaction kinetics, herein, a carbon nanolayer conformally coated Fe2 O3 (C-Fe2 O3 ) as oxygen evolution catalyst (OEC) is loaded on the H2 plasma treated nanoporous BiVO4 (BVO(H2 )) surface by a hydrothermal reaction. It is found that the H2 plasma induced vacancies in BVO remarkably increases the conductivity, and the C-Fe2 O3 enables hole extraction from the bulk to the surface as well as efficient hole injection to the electrolyte. As a result, the C-Fe2 O3 /BVO(H2 ) photoanode achieves a photocurrent density of 4.4 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (RHE) and an ABPE value of 1.5 % at 0.68 V vs. RHE, which are 4.8-fold and 13-fold higher than that of BVO photoanode, respectively.

10.
Chemistry ; 29(71): e202302398, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-37728302

RESUMO

Electrocatalytic water splitting is one of the most commercially valuable pathways of hydrogen production especially combined with renewable electricity; however, efficient and durable electrocatalysts are urgently needed to reduce electric energy consumption. Here, we reported a Ru and Fe co-doped Mo2 C on nitrogen doped carbon via a controllable two-step method, which can be used for efficient and enduring hydrogen evolution reaction. At 10, 100 and 200 mA cm-2 in acidic electrolyte, the resultant Ru-Fe/Mo2 C@NC delivered low overpotentials of 31, 78 and 103 mV, respectively, which are comparable to that of the commercial Pt/C (20 wt %). At an applied current density of 100 mA cm-2 , stable hydrogen production was conducted for 120 h without obvious degradation. In alkaline media, Ru-Fe/Mo2 C@NC can also deliver a current density of 100 mA cm-2 for more than 100 h. Furthermore, the Ru-Fe/Mo2 C@NC electrocatalyst was used as cathode in an anion exchange membrane water electrolyzer under industrial environments for robust hydrogen production. The characterization and electrochemical results prove the synergism effects between Ru, Fe dopants and Mo2 C for promoting hydrogen evolution activity. This work would pave a new avenue to fabricate low-cost, high-performance hydrogen evolution electrocatalysts for industrial water electrolyzers.

11.
Chemphyschem ; 24(8): e202200657, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36646629

RESUMO

The discovery of high-performance catalysts for the electrochemical CO2 reduction reaction (CO2 RR) has faced an enormous challenge for years. The lack of cognition about the surface active structures or centers of catalysts in complex conditions limits the development of advanced catalysts for CO2 RR. Recently, the positive valent metal sites (PVMS) are demonstrated as a kind of potential active sites, which can facilitate carbon dioxide (CO2 ) activation and conversation but are always unstable under reduction potentials. Many advanced technologies in theory and experiment have been utilized to understand and develop excellent catalysts with PVMS for CO2 RR. Here, we present an introduction of some typical catalysts with PVMS in CO2 RR and give some understanding of the activity and stability for these related catalysts.

12.
Genomics ; 114(1): 328-339, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34933071

RESUMO

Aeromonas salmonicida (A. salmonicida) is a pathogenic bacterium that causes serious problems in the global Atlantic salmon aquaculture industry. In this study, we comprehensively analyzed the profiles of lncRNAs, miRNAs and mRNAs in gills of Atlantic salmon at high-dose A. salmonicida infection (3.06 × 108 CFU/mL), low-dose A. salmonicida infection (3.06 × 105 CFU/mL), and a PBS (100 µL) control. We identified 65 differentially expressed lncRNAs, 41 miRNAs, and 512 mRNAs between the control group and infection groups. Functional analysis showed that these genes were significantly enriched in the p53 signaling pathway, Wnt signaling pathway, mTOR signaling pathway, JAK-STAT signaling pathway, and Toll-like receptor signaling pathway. In addition, we predicted key genes in immune-related pathways and constructed a lncRNA-miRNA-mRNA network based on whole transcriptomic analysis. We further predicted three lncRNA-miRNA-mRNA axes as potential novel biomarkers in regulating the immune response of Atlantic salmon against A. salmonicida infection.


Assuntos
Aeromonas salmonicida , MicroRNAs , RNA Longo não Codificante , Salmo salar , Aeromonas salmonicida/genética , Aeromonas salmonicida/metabolismo , Animais , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Salmo salar/genética , Salmo salar/metabolismo
13.
Sheng Li Xue Bao ; 75(6): 877-886, 2023 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-38151350

RESUMO

The imbalance of redox homeostasis is a major characteristic of aging and contributes to the pathogenesis of various aging-related diseases. As a regulatory hub of redox homeostasis, nuclear factor erythroid 2-related factor 2 (NRF2) can attenuate oxidative stress by activating the transcription of many antioxidant enzymes. China is the birthplace of traditional Chinese medicine (TCM) which has been wildly used as medicine for thousands of years. Recently, TCM as anti-aging medicine has attracted enormous attention. Focusing on the NRF2 signaling pathway, this paper summarizes the correlation between various anti-aging TCM and the NRF2 signaling, and discusses the common key mechanisms by which TCM slows the aging process by targeting the NRF2 signaling network.


Assuntos
Medicina Tradicional Chinesa , Fator 2 Relacionado a NF-E2 , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais
14.
Zhonghua Nan Ke Xue ; 29(4): 298-305, 2023 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38598212

RESUMO

OBJECTIVE: To explore the potential action mechanisms of Xiaoluowan (II) (XLW-II) in the treatment of epididymitis through a network pharmacology approach. METHODS: We searched various databases for relevant targets associated with epididymitis and XLW-II and obtained the common targets of epididymitis and XLW-II on the Venny platform. We acquired the protein-protein interactions (PPI) using the STRING data and had them visualized with the Cytoscape software. After topological analysis, we retrieved the key targets, followed by gene ontology (GO) and KEGG pathway enrichment analyses using the DAVID database. RESULTS: A total of 2 38 drug targets, 2 150 disease targets and 85 common targets were identified. The core targets for the treatment of epididymitis with XLW-II identified by PPI network analysis included TNF, IL6, IL1B, MMP9, AKT1, PTGS2 and TP53. GO function analysis revealed the involvement of the common targets in such biological processes as response to hypoxia, regulation of apoptotic processes, inflammatory response, and positive regulation of the MAPK cascade. KEGG pathway analysis suggested that the signaling pathways such as the cancer pathway, PI3K-Akt pathway, protein glycosylation pathway in cancer, Ras pathway and chemokine pathway might be related to the action mechanisms of XLW-II in the treatment of epididymitis. CONCLUSION: The potential targets and signaling pathways of Xiaoluowan (II) in the treatment of epididymitis were identified on the basis of network pharmacology, which has provided a novel insight into its action mechanisms and offered a new direction for further relevant studies.


Assuntos
Medicamentos de Ervas Chinesas , Epididimite , Neoplasias , Masculino , Humanos , Epididimite/tratamento farmacológico , Farmacologia em Rede , Fosfatidilinositol 3-Quinases
15.
Zhonghua Nan Ke Xue ; 29(9): 783-789, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-38639589

RESUMO

Objective: To explore the mechanism of Miao ethnicity medicine formula of Oxalis corniculata against chronic non-bacterial prostatitis. Methods: The rat model of chronic abacterial prostatitis was induced by stimulation with 2% sterile carrageenan solution. After modeling, the rats were randomly divided into two groups, Model control group (Model group) and oxalis group. Another normal control group was set up. The rats in the Model group and the normal control group were given 0.01ml/g normal saline by gavage, and the rats in the oxalis alis group were given 1ml/100g (1 g/kg) of Oxalis corniculata L warm water decoction by gavage once a day for 28 days. Twenty-four hours after the last administration, 10ml blood was collected from the abdominal aorta of the rats, and prostate tissue samples were collected from the rats. hematoxylin-eosin (HE) staining was used to observe the morphological structure of the prostate in normal and prostatitis rats. ELISA was used to detect the levels of serum and prostate cytokines. The protein expressions of 4-HNE , ALDH2 and FGF2 were detected by Western blot. Results: Compared with the blank group, the model group showed obvious hyperplasia of fibrous tissue in the interstitium of the prostate tissue, disordered glandular structure, papillary hyperplasia of epithelial cells in the acini, infiltration of a small amount of lymphocytes, monocytes and other inflammatory cells in the acini, and increased pathological scores. The protein expressions of 4-HNE , ALDH2 , MCP-1 and FGF2 in prostate tissue were significantly increased. Compared with the model group, the prostate tissue of the oxalis group was slightly damaged, with a small amount of fibrous hyperplasia and inflammatory cell infiltration. The protein expressions of 4-HNE , ALDH2 , MCP-1 and FGF2 were decreased in prostate tissue. Conclusion: Oxalis corniculata L can effectively repair the pathological morphology of prostate tissue in rats with CNP, and its mechanism may be related to activating 4-HNE protein and reducing oxidative stress injury of prostate tissue in rats.


Assuntos
Oxalidaceae , Prostatite , Masculino , Humanos , Ratos , Animais , Prostatite/patologia , Hiperplasia , Etnicidade , Fator 2 de Crescimento de Fibroblastos , Aldeído-Desidrogenase Mitocondrial
16.
Zhonghua Nan Ke Xue ; 29(8): 698-704, 2023 Aug.
Artigo em Zh | MEDLINE | ID: mdl-38619515

RESUMO

OBJECTIVE: To explore the potential mechanism of action of levocarnitine in the treatment of epididymitis based on network pharmacology and experimental research. METHODS: The target proteins related to epididymitis and levocarnitine were retrieved through multiple databases, and the common targets were obtained using Venny software. The protein-protein interactions were obtained using the STRING database. Cytoscape software was used for visualization, and key targets were selected after topological analysis. GO and KEGG pathway enrichment analysis was performed using the DAVID database. Molecular docking was performed using Autodock Vina. RESULTS: A total of 130 drug targets and 2 151 disease targets were obtained, with 47 common targets. Protein-protein interaction network analysis identified core targets of levocarnitine in the treatment of epididymitis, including AKT1, HSP90AA1, ALB, CASP3, GSK3B, and GSR. KEGG pathway analysis suggested that metabolic pathways, lipid metabolism and atherosclerosis, cancer pathways, fluid shear stress and atherosclerosis, measles, chemical carcinogens-reactive oxygen species, purine metabolism, PI3K-Akt, and other signaling pathways may be associated with the mechanism of levocarnitine in the treatment of epididymitis. CONCLUSION: This study revealed through network pharmacology that levocarnitine may act on multiple signaling pathways by targeting AKT1, HSP90AA1, ALB, CASP3, GSK3B, GSR, etc., thereby potentially exerting therapeutic effects on epididymitis.


Assuntos
Aterosclerose , Epididimite , Masculino , Humanos , Simulação de Acoplamento Molecular , Carnitina , Farmacologia em Rede , Caspase 3 , Fosfatidilinositol 3-Quinases
17.
Zhonghua Nan Ke Xue ; 29(3): 202-209, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38597700

RESUMO

OBJECTIVE: To investigate the biological mechanisms underlying the effect of the Chinese herbal medicine Oxalis corniculata on human prostate cancer PC-3 cells. METHODS: Through in vitro experiment, we treated human prostate cancer PC-3 cells with different concentrations of Oxalis corniculata, assessed the viability of the cells by MTT assay, examined their apoptosis by flow cytometry, evaluated their migration and invasiveness by Transwell assay, and determined the expressions of the proteins p65, p-p65, IκBα and p-IκBα in the NF-κB pathway using protein imprinting technology. RESULTS: Compared with the blank control, Oxalis corniculata significantly inhibited the proliferation and induced the apoptosis of the PC-3 cells (P< 0.05), suppressed their migration and invasiveness in a dose-dependent manner (P< 0.05), and upregulated the expression of IκBα and downregulated those of p-p65 and p-IκBα in the NF-κB pathway (P< 0.05). CONCLUSION: Oxalis corniculata can inhibit the proliferation, migration and invasiveness and induce the apoptosis of human prostate cancer PC cells, which may be attributed to its abilities of inhibiting the expressions of p-p65 and p-IκBα and regulating the activity of the NF-κB pathway.


Assuntos
Oxalidaceae , Neoplasias da Próstata , Masculino , Humanos , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/farmacologia , Células PC-3 , Oxalidaceae/metabolismo , Neoplasias da Próstata/metabolismo , Apoptose
18.
Zhonghua Nan Ke Xue ; 29(6): 483-489, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38602719

RESUMO

OBJECTIVE: This study aimed to investigate the mechanism of Xiaoluanwan(II) in treating lipopolysaccharide(LPS)-induced epididymitis and its impact on the NLRP3 inflammasome. METHODS: The murine epididymitis model was established through local injection of LPS. The study included a control group (n=5), a model group (n=5), a model group treated with Xiaoluanwan(II) (Ⅱ) (n=5), and a saline group treated with Xiaoluanwan(II) (n=5). After 14 consecutive days of oral administration of Xiaoluanwan(II) or physiological saline, pathological changes in the epididymal tissues, expression levels of NLRP3 inflammasome and Caspase-1, as well as associated protein levels were examined. RESULTS: Compared to the model group, Xiaoluanwan(II) significantly alleviated inflammatory cell infiltration and lesions, as evidenced by a reduction in the protein expression levels of NLRP3, Caspase-1, Cleaved-Caspase-1, IL-1ß, IL-18, GSDMD, and p-p38 MAPK (P<0.05 or P<0.01), thereby mitigating the inflammatory response. CONCLUSION: Xiaoluanwan(II) alleviates epididymal inflammation and ameliorates mouse epididymal epithelial injury by modulating the NLRP3-mediated cell pyroptosis pathway.


Assuntos
Epididimite , Inflamassomos , Masculino , Humanos , Animais , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Epididimite/tratamento farmacológico , Lipopolissacarídeos , Caspase 1 , Solução Salina
19.
Angew Chem Int Ed Engl ; 62(19): e202217296, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36912381

RESUMO

The electrocatalytic reduction of carbon dioxide provides a feasibility to achieve a carbon-neutral energy cycle. However, there are a number of bottleneck issues to be resolved before industrial application, such as the low conversion efficiency, selectivity and reaction rate, etc. Engineering local environment is a critical way to address these challenges. Here, a monolayer MgAl-LDH was proposed to optimize the local environment of Cu for stimulating industrial-current-density CO2 -to-C2 H4 electroreduction in neutral media. In situ spectroscopic results and theoretical study demonstrated that the Cu electrode modified by MgAl-LDH (MgAl-LDH/Cu) displayed a much higher surface pH value compared to the bare Cu, which could be attributed to the decreased energy barrier for hydrolysis on MgAl-LDH sites with more OH- ions on the surface of the electrode. As a result, MgAl-LDH/Cu achieved a C2 H4 Faradaic efficiency of 55.1 % at a current density up to 300 mA cm-2 in 1.0 M KHCO3 electrolyte.

20.
J Am Chem Soc ; 144(13): 6028-6039, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35302356

RESUMO

Water-alkaline electrolysis holds a great promise for industry-scale hydrogen production but is hindered by the lack of enabling hydrogen evolution reaction electrocatalysts to operate at ampere-level current densities under low overpotentials. Here, we report the use of hydrogen spillover-bridged water dissociation/hydrogen formation processes occurring at the synergistically hybridized Ni3S2/Cr2S3 sites to incapacitate the inhibition effect of high-current-density-induced high hydrogen coverage at the water dissociation site and concurrently promote Volmer/Tafel processes. The mechanistic insights critically important to enable ampere-level current density operation are depicted from the experimental and theoretical studies. The Volmer process is drastically boosted by the strong H2O adsorption at Cr5c sites of Cr2S3, the efficient H2O* dissociation via a heterolytic cleavage process (Cr5c-H2O* + S3c(#) → Cr5c-OH* + S3c-H#) on the Cr5c/S3c sites in Cr2S3, and the rapid desorption of OH* from Cr5c sites of Cr2S3 via a new water-assisted desorption mechanism (Cr5c-OH* + H2O(aq) → Cr5c-H2O* + OH-(aq)), while the efficient Tafel process is achieved through hydrogen spillover to rapidly transfer H# from the synergistically located H-rich site (Cr2S3) to the H-deficient site (Ni3S2) with excellent hydrogen formation activity. As a result, the hybridized Ni3S2/Cr2S3 electrocatalyst can readily achieve a current density of 3.5 A cm-2 under an overpotential of 251 ± 3 mV in 1.0 M KOH electrolyte. The concept exemplified in this work provides a useful means to address the shortfalls of ampere-level current-density-tolerant Hydrogen evolution reaction (HER) electrocatalysts.

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