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1.
Proc Natl Acad Sci U S A ; 120(3): e2217148120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36630453

RESUMO

Modulation of water activation is crucial to water-involved chemical reactions in heterogeneous catalysis. Organic sulfur (COS and CS2) hydrolysis is such a typical reaction involving water (H2O) molecule as a reactant. However, limited by the strong O-H bond in H2O, satisfactory CS2 hydrolysis performance is attained at high temperature above 310 °C, which is at the sacrifice of the Claus conversion, strongly hindering sulfur recovery efficiency improvement and pollution emissions control of the Claus process. Herein, we report a facile oxygen vacancy (VO) engineering on titanium-based perovskite to motivate H2O activation for enhanced COS and CS2 hydrolysis at lower temperature. Increased amount of VO contributed to improved degree of H2O dissociation to generate more active -OH, due to lower energy barrier for H2O dissociation over surface rich in VO, particularly VO clusters. Besides, low-coordinated Ti ions adjacent to VO were active sites for H2O activation. Consequently, complete conversion of COS and CS2 was achieved over SrTiO3 after H2 reduction treatment at 225 °C, a favorable temperature for the Claus conversion, at which both satisfying COS and CS2 hydrolysis performance and improved sulfur recovery efficiency can be obtained simultaneously. Additionally, the origin of enhanced hydrolysis activity from boosted H2O activation by VO was revealed via in-depth mechanism study. This provides more explicit direction for further design of efficacious catalysts for H2O-involved reactions.


Assuntos
Oxigênio , Titânio , Temperatura , Hidrólise , Água/química , Enxofre
2.
J Cell Mol Med ; 28(8): e18256, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38527290

RESUMO

Acute myeloid leukaemia (AML) is a prevalent haematological malignancy in which various immune and stromal cells in the bone marrow microenvironment have instrumental roles and substantially influence its progression. KIR2DL is a member of the immunoglobulin-like receptor family and a natural killer (NK) cell surface-specific receptor. However, its impact on immune infiltration regarding AML has not been addressed. We aimed to explore molecular markers associated with the immune microenvironment and prognosis of AML with a particular focus on KIR2DL family members. Analysis of data from The Cancer Genome Atlas and Genotype-Tissue Expression databases revealed that KIR2DL1, KIR2DL3 and KIR2DL4 expression were significantly upregulated in AML and associated with decreased overall survival (OS). Moreover, univariate Cox analysis implicated KIR2DL genes as independent prognostic markers of OS. Functional enrichment analysis revealed that KIR2DL genes were associated with immune cells, the immune microenvironment and NK cell-mediated cytotoxicity. Additionally, immune infiltration analyses revealed that KIR2DL upregulation was associated with stronger immune infiltration. Finally, we performed drug sensitivity profiling of KIR2DL genes using the Cellminer database. Collectively, our findings suggest that KIR2DL1, KIR2DL3 and KIR2DL4 have critical roles in AML and may represent novel biomarker genes for disease prognosis and immune infiltration.


Assuntos
Leucemia Mieloide Aguda , Humanos , Prognóstico , Leucemia Mieloide Aguda/patologia , Medula Óssea/patologia , Microambiente Tumoral/genética
3.
Environ Sci Technol ; 58(4): 2153-2161, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38244211

RESUMO

Nitrous oxide (N2O) has a detrimental impact on the greenhouse effect, and its efficient catalytic decomposition at low temperatures remains challenging. Herein, the cobalt-based high-entropy oxide with a spinel-type structure (Co-HEO) is successfully fabricated via a facile coprecipitation method for N2O catalytic decomposition. The obtained Co-HEO catalyst displays more remarkable catalytic performance and higher thermal stability compared with single and binary Co-based oxides, as the temperature of 90% N2O decomposition (T90) is 356 °C. A series of characterization results reveal that the synergistic effect of multiple elements enhances the reducibility and augments oxygen vacancy in the high-entropy system, thus boosting the activity of the Co-HEO catalyst. Moreover, density functional theory (DFT) calculations and the temperature-programmed surface reaction (TPSR) with isotope labeling demonstrate that N2O decomposition on the Co-HEO catalyst follows the Langmuir-Hinshelwood (L-H) mechanism with the promotion of abundant oxygen vacancies. This work provides a fundamental understanding of the synergistic catalytic effect in N2O decomposition and paves the way for the novel environmental catalytic applications of HEO.


Assuntos
Cobalto , Óxidos , Entropia , Óxidos/química , Cobalto/química , Oxigênio
4.
Environ Sci Technol ; 58(9): 4428-4437, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38400916

RESUMO

The adsorption and activation of pollutant molecules and oxygen play a critical role in the oxidation reaction of volatile organic compounds (VOCs). In this study, superior adsorption and activation ability was achieved by modulating the interaction between Pt nanoparticles (NPs) and UiO-66 (U6) through the spatial position effect. Pt@U6 exhibits excellent activity in toluene, acetone, propane, and aldehyde oxidation reactions. Spectroscopic studies, 16O2/18O2 kinetic isotopic experiments, and density functional theory (DFT) results jointly reveal that the encapsulated Pt NPs of Pt@U6 possess higher electron density and d-band center, which is conducive for the adsorption and dissociation of oxygen. The toluene oxidation reaction and DFT results indicate that Pt@U6 is more favorable to activate the C-H of toluene and the C═C of maleic anhydride, while Pt/U6 with lower electron density and d-band center exhibits a higher oxygen dissociation temperature and higher reactant activation energy barriers. This study provides a deep insight into the architecture-performance relation of Pt-based catalysts for the catalytic oxidation of VOCs.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ácidos Ftálicos , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/química , Tolueno/química , Oxigênio
5.
Angew Chem Int Ed Engl ; 63(16): e202400627, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38390644

RESUMO

Metal-modified catalysts have attracted extraordinary research attention in heterogeneous catalysis due to their enhanced geometric and electronic structures and outstanding catalytic performances. Silver (Ag) possesses necessary active sites for ethylene epoxidation, but the catalyst activity is usually sacrificed to obtain high selectivity towards ethylene oxide (EO). Herein, we report that using Al can help in tailoring the unoccupied 3d state of Ag on the MnO2 support through strong electronic metal-support interactions (EMSIs), overcoming the activity-selectivity trade-off for ethylene epoxidation and resulting in a very high ethylene conversion rate (~100 %) with 90 % selectivity for EO under mild conditions (170 °C and atmospheric pressure). Structural characterization and theoretical calculations revealed that the EMSIs obtained by the Al modification tailor the unoccupied 3d state of Ag, modulating the adsorption of ethylene (C2H4) and oxygen (O2) and facilitating EO desorption, resulting in high C2H4 conversion. Meanwhile, the increased number of positively charge Ag+ lowers the energy barrier for C2H4(ads) oxidation to produce oxametallacycle (OMC), inducing the unexpectedly high EO selectivity. Such an extraordinary electronic promotion provides new promising pathways for designing advanced metal catalysts with high activity and selectivity in selective oxidation reactions.

6.
J Am Chem Soc ; 145(12): 6658-6670, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36802612

RESUMO

Developing efficient and simple catalysts to reveal the key scientific issues in the epoxidation of ethylene has been a long-standing goal for chemists, whereas a heterogenized molecular-like catalyst is desirable which combines the best aspects of homogeneous and heterogeneous catalysts. Single-atom catalysts can effectively mimic molecular catalysts on account of their well-defined atomic structures and coordination environments. Herein, we report a strategy for selective epoxidation of ethylene, which exploits a heterogeneous catalyst comprising iridium single atoms to interact with the reactant molecules that act analogously to ligands, resulting in molecular-like catalysis. This catalytic protocol features a near-unity selectivity (99%) to produce value-added ethylene oxide. We investigated the origin of the improvement of selectivity for ethylene oxide for this iridium single-atom catalyst and attributed the improvement to the π-coordination between the iridium metal center with a higher oxidation state and ethylene or molecular oxygen. The molecular oxygen adsorbed on the iridium single-atom site not only helps to strengthen the adsorption of ethylene molecule by iridium but also alters its electronic structure, allowing iridium to donate electrons into the double bond π* orbitals of ethylene. This catalytic strategy facilitates the formation of five-membered oxametallacycle intermediates, leading to the exceptionally high selectivity for ethylene oxide. Our model of single-atom catalysts featuring remarkable molecular-like catalysis can be utilized as an effective strategy for inhibiting the overoxidation of the desired product. Implementing the concepts of homogeneous catalysis into heterogeneous catalysis would provide new perspectives for the design of new advanced catalysts.

7.
Small ; : e2308468, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38009497

RESUMO

Developing deep-blue emitters for organic light-emitting diodes (OLEDs) is critical but challenging, which requires a good balance between light color, exciton utilization, and photoluminescence quantum yield (PLQY) of solid film. Herein, a high-quality deep-blue emitter, abbreviated 2TriPE-CzMCN, is designed by introducing an aggregation-induced emission (AIE) group into a crossed long-short axis (CLSA) skeleton. Theoretical and experimental investigations reveal that the CLSA molecular design can achieve a balance between deep-blue emission and triplet-excitons utilization, while the high PLQY of the solid film resulting from the AIE feature helps to improve the performance of OLEDs. Consequently, when 2TriPE-CzMCN is used as the emitting dopant, the OLED exhibits a deep-blue emission at 430 nm with a record-high maximum external quantum efficiency (EQE) of 8.84%. When 2TriPE-CzMCN serves as the host material, the sensitized monochrome orange and two-color white OLEDs (WOLEDs) realize high EL performances that exceed the efficiency limit of conventional fluorescent OLEDs. Moreover, high-performance three-color WOLEDs with a color rendering index (CRI) exceeding 90 and EQE up to 18.08% are achieved by using 2TriPE-CzMCN as the blue-emitting source. This work demonstrates that endowing CLSA molecule with AIE feature is an effective strategy for developing high-quality deep-blue emitters, and high-performance versatile OLEDs can be realized through rational device engineering.

8.
Opt Express ; 31(7): 11923-11939, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155816

RESUMO

This work aims to enhance the physical layer security (PLS) of non-orthogonal multiple access (NOMA) aided indoor visible light communication (VLC) system with semi-grant-free (SGF) transmission scheme, in which a grant-free (GF) user shares the same resource block with a grant-based (GB) user whose quality of service (QoS) must be strictly guaranteed. Besides, the GF user is also provided with an acceptable QoS experience, which is closely aligned with the practical application. Both active and passive eavesdropping attacks are discussed in this work, where users' random distributions are taken into account. Specifically, to maximize the secrecy rate of the GB user in the presence of an active eavesdropper, the optimal power allocation policy is obtained in exact closed-form and the user fairness is then assessed by Jain's fairness index. Moreover, the secrecy outage performance of the GB user is analyzed in the presence of the passive eavesdropping attack. Both exact and asymptotic theoretical expressions for the secrecy outage probability (SOP) of the GB user are derived, respectively. Furthermore, the effective secrecy throughput (EST) is investigated on the basis of the derived SOP expression. Through simulations, it is found that the PLS of this VLC system can be significantly improved by the proposed optimal power allocation scheme. The radius of the protected zone, the outage target rate for the GF user, and the secrecy target rate for the GB user would have pronounced impacts on the PLS and user fairness performance of this SGF-NOMA assisted indoor VLC system. The maximum EST will increase with the increasing transmit power and it is hardly influenced by the target rate for the GF user. This work will benefit the design of indoor VLC system.

9.
Opt Express ; 31(21): 34729-34747, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859223

RESUMO

Although underwater wireless optical communication (UWOC) receives much interest lately, security issues associated with it get little attention. In this work, it is the first attempt to investigate the physical layer security (PLS) performance of the vertical UWOC system with perfect and imperfect channel state information (CSI). Specifically speaking, the communication between two legitimate peers in the presence of an external eavesdropper is studied from the information-theoretic security perspective. Assuming that turbulence-induced fading over the vertical UWOC links is respectively subject to cascaded lognormal (LN) and Gamma-Gamma (GG) distributions for weak and moderate/strong turbulence conditions, and the angular pointing error is randomized by the Beckmann distribution, the composite cascaded statistical fading models are derived with the comprehensive effects of path loss, underwater turbulence, angular pointing errors, and channel estimation error. On the basis of these models, analysis frameworks of the probability of strictly positive secrecy capacity (SPSC), secrecy outage probability (SOP), and average secrecy capacity (ASC) are further obtained for this UWOC system, which are confirmed by Monte Carlo (MC) simulations. Furthermore, the effects including the number of layers, the level of channel estimation error, the link distance, the location of the eavesdropper, the quality of the main and eavesdropping channels on this system are analyzed for different water conditions. The presented results give valuable insights into the practical aspects of deployment of UWOC networks.

10.
Small ; 18(41): e2204029, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36084169

RESUMO

In this work, a near-ultraviolet (NUV) emitter, 2MCz-CNMCz, with hot-exciton property is designed based on a "long-short axis" strategy, which exhibits good thermal stability, bipolar carrier transport ability, and high T1 energy level. Its nondoped NUV organic light-emitting diode (OLED) achieves a record maximum external quantum efficiency (ηext ) of 7.76%, with a peak at 404 nm and CIE coordinates of (0.158, 0.039). The corresponding high exciton utilization efficiency (ηr ) in the electroluminescence process reveals its potential as a functional sensitizing host. As expected, the TBPe-based blue fluorescent OLED with 2MCz-CNMCz as the host material shows better efficiency and lower efficiency roll-off than that with traditional host material mCP. Meanwhile, the Ir complexes-based green/yellow/red phosphorescent OLEDs with 2MCz-CNMCz host are also fabricated, reaching high ηext values of 26.1%, 30.4%, and 20.4%, respectively, and displaying negligible efficiency roll-offs at 1000 cd m-2 , which are among the best OLED performances based on the same emitters. To the authors' best knowledge, this is the first report on the design of high-quality universal and functional host material, and may bring new inspiration to the preparation of high-efficiency, low roll-off, full-color OLEDs.

11.
Appl Opt ; 61(35): 10390-10399, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36607097

RESUMO

The intelligent reflecting surface (IRS) and angle diversity receiver (ADR) jointly assisted indoor visible light communication (VLC) system is proposed to improve average signal-to-noise ratio (ASNR) performance. Specifically, to maximize the ASNR at the receiving plane, the roll angle and yaw angle of IRS and the inclination angle of the side detector in the ADR structure are optimized simultaneously as one non-convex problem. With the bat algorithm, the optimal solution is numerically obtained. Results show that when the transmit power of the light emitting diode lamp array is 1 W, the ASNRs of this VLC system optimized by IRS and ADR are approximately 7.89 dB, 3.58 dB, and 2.09 dB higher than those of the original, IRS-assisted, and ADR-assisted VLC systems, respectively. Furthermore, the transmission rate and bit error rate performances of the original, IRS-assisted, ADR-assisted, and IRS and ADR jointly assisted indoor VLC systems are also simulated and compared; it is found that the performance improvement of the indoor VLC system jointly optimized by IRS and ADR is more evident than that of the other three VLC systems. This study will benefit the research and development of indoor VLC systems.

12.
Angew Chem Int Ed Engl ; 61(48): e202209425, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36200442

RESUMO

Narrowband emitting fluorophores exhibit immense potentials for organic light-emitting diodes (OLEDs) with high color purity. However, it's still hard to simultaneously realize short-wavelength ultraviolet (UV) or near ultraviolet emission (NUV) while maintaining a narrowed full width at half maximum (FWHM) value, and rare work focus on such challenging pursuit. Herein, an ingenious synthetic method was devised to achieve emitters with coplanar structure. 11-(4,6-diphenyl-1,3,5-triazin-2-yl)indolo[3,2,1-jk]carbazole (ICZ-TAZ) was designed to realize narrowed UV emission both in photoluminescence (PL) and electroluminescence (EL) which benefited from the suppression of vibronic coupling. UV/NUV OLEDs based on ICZ-TAZ achieve external quantum efficiency (EQE) maximums of 3.26 % peaks @ 388 nm and 4.02 % peaks @ 406 nm with small FWHM of 32 nm and 46 nm, respectively, corresponding with reduced efficiency roll-off at luminance of 100 cd m-2 .

13.
Angew Chem Int Ed Engl ; 60(22): 12376-12380, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33768658

RESUMO

Spiro-acridan (SpA) derivatives possess a great potential in preparing efficient thermally activated delayed fluorescent (TADF) emitters. However, the conventional synthetic routes are cost-expensive and time-consuming. The development of a simple procedure to synthesize SpAs is still in urgent pursuing appreciated by academic and industrial communities. In this contribution, we present a feasible acid-catalyzed solvent-free metal-free cyclization between diarylamines and ketones to construct SpAs. The as-constructed moieties provide a wide possibility to assemble efficient TADF emitters. As an example, D2T-TR with high photoluminescent quantum yield and proper TADF character is applied in organic light emitting diodes (OLEDs) which achieves a maximum external quantum efficiency (EQE) of 27.1 %. This work shows us a bright inspiration on developing excellent organic optoelectronic materials and an effective tool to realize it.

14.
Angew Chem Int Ed Engl ; 60(41): 22241-22247, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34387938

RESUMO

Ultraviolet (UV) organic emitters that can open up applications for future organic light-emitting diodes (OLEDs) are of great value but rarely developed. Here, we report a high-quality UV emitter with hybridized local and charge-transfer (HLCT) excited state and its application in UV OLEDs. The UV emitter, 2BuCz-CNCz, shows the features of low-lying locally excited (LE) emissive state and high-lying reverse intersystem crossing (hRISC) process, which helps to balance the color purity and exciton utilization of UV OLED. Consequently, the OLED based on 2BuCz-CNCz exhibits not only a desired narrowband UV electroluminescent (EL) at 396 nm with satisfactory color purity (CIEx, y =0.161, 0.031), but also a record-high maximum external quantum efficiency (EQE) of 10.79 % with small efficiency roll-off. The state-of-the-art device performance can inspire the design of UV emitters, and pave a way for the further development of high-performance UV OLEDs.

15.
Zhongguo Zhong Yao Za Zhi ; 39(14): 2732-8, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25272505

RESUMO

Coptidis Rhizoma and Aconiti Kusnezoffii Radix represent hot Chinese medicine and cold Chinese medicine respectively. The purpose of this study is to observe the differentiation effect of Coptidis Rhizoma and Aconiti Kusnezoffii Radix on lewis lung cancer and compare effect of hot Chinese medicine and cold Chinese medicine on tumor progression. In this study, the rat serum containing Coptidis Rhizoma or Aconiti Kusnezoffii Radix was prepared to treat lewis lung cancer cells in vitro, and effects of the serum containing Coptidis Rhizoma or Aconiti Kusnezoffii Radix on cell differentiation, proliferation, adhesion, succinic dehydrogenase (SDH) activity and gap-junction intercellular communication (GJIC) were investigated. In vivo, the subcutaneous implant model and pulmonary metastasis model of lewis lung cancer were established. Tumor bearing mice were taken water decoction of coptis chinensis or aconite by intragastric administration bid for four weeks, and the influences of coptis chinensis and aconite on tumor progression were evaluated by body temperature, blood oxygen saturation, red cell ATPase, blood rheology, intratumor hypoxia, capillary permeability and GJIC. The results showed that the serum containing aconite could induce cell differentiation, inhibit cell proliferation and migration, promote SDH activity and GJIC in lewis lung cancer cells. The serum containing Coptidis Rhizoma increased cell adhesion and decreased SDH activity and GJIC without cell differentiation although it also suppressed cell proliferation. Aconiti Kusnezoffii Radix water decoction could keep body temperature, blood oxygen saturation, red cell ATPase and blood rheology, and improve intratumor hypoxia, capillary permeability and GJIC in tumor bearing mice, which led to slower tumor growth and less metastasis. Coptidis Rhizoma water decoction decreased body temperature, blood oxygen saturation, red cell ATPase, blood rheology and GJIC, and promoted intratumor hypoxia and capillary permeability, which resulted to more tumor metastasis although it also prevented tumor growth. These results suggested that the hot Chinese medicine could induce tumor cell differentiation and prevent tumor poison invagination, which is better for tumor treatment than cold Chinese medicine.


Assuntos
Aconitum/química , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Lewis/patologia , Diferenciação Celular/efeitos dos fármacos , Curcuma/química , Medicamentos de Ervas Chinesas/farmacologia , Animais , Linhagem Celular Tumoral , Camundongos , Metástase Neoplásica , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Pharm Biomed Anal ; 243: 116061, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430615

RESUMO

BACKGROUND: Diabetes mellitus type 2 and pulmonary fibrosis have been found to be closely related in clinical practice. Diabetic pulmonary fibrosis (DPF) is a complication of diabetes mellitus, but its treatment has yet to be thoroughly investigated. Bu Yang Huan Wu Decoction (BYHWD) is a well-known traditional Chinese prescription that has shown great efficacy in treating pulmonary fibrosis with hypoglycemic and hypolipidemic effects. METHODS: The active ingredients of BYHWD and the corresponding targets were retrieved from the Traditional Chinese Medicine Systematic Pharmacology Database (TCMSP) and SymMap2. Disease-related targets were obtained from the GeneCard, OMIM and CTD databases. GO enrichment and KEGG pathway enrichment were carried out using the DAVID database. AutoDock Vina software was employed to perform molecular docking. Molecular dynamics simulations of proteinligand complexes were conducted by Gromacs. Animal experiments were further performed to validate the effects of BYHWD on the selected core targets, markers of oxidative stress, serum lipids, blood glucose and pulmonary fibrosis. RESULTS: A total of 84 active ingredients and 830 target genes were screened in BYHWD, among which 56 target genes intersected with DPF-related targets. Network pharmacological analysis revealed that the active ingredients can regulate target genes such as IL-6, TNF-α, VEGFA and CASP3, mainly through AGE-RAGE signaling pathway, HIF-1 signaling pathway and TNF signaling pathway. Molecular docking and molecular dynamics simulations suggested that IL6-astragaloside IV, IL6-baicalein, TNFα-astragaloside IV, and TNFα-baicalein docking complexes could bind stably. Animal experiments showed that BYHWD could reduce the expression of core targets such as VEGFA, CASP3, IL-6 and TNF-α. In addition, BYHWD could reduce blood glucose, lipid, and MDA levels in DPF while increasing the activities of SOD, CAT and GSH-Px. BYHWD attenuated the expression of HYP and collagen I, mitigating pathological damage and collagen deposition within lung tissue. CONCLUSIONS: BYHWD modulates lipid metabolism disorders and oxidative stress by targeting the core targets of IL6, TNF-α, VEGFA and CASP3 through the AGE-RAGE signaling pathway, making it a potential therapy for DPF.


Assuntos
Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Transtornos do Metabolismo dos Lipídeos , Fibrose Pulmonar , Saponinas , Triterpenos , Animais , Fator de Necrose Tumoral alfa , Fibrose Pulmonar/tratamento farmacológico , Caspase 3 , Interleucina-6 , Glicemia , Metabolismo dos Lipídeos , Simulação de Acoplamento Molecular , Estresse Oxidativo , Colágeno , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
17.
Chin J Integr Med ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941045

RESUMO

OBJECTIVE: To observe the therapeutic effects and underlying mechanism of baicalin against colon cancer. METHODS: The effects of baicalin on the proliferation and growth of colon cancer cells MC38 and CT26. WT were observed and predicted potential molecular targets of baicalin for colon cancer therapy were studied by network pharmacology. Furthermore, molecular docking and drug affinity responsive target stability (DARTS) analysis were performed to confirm the interaction between potential targets and baicalin. Finally, the mechanisms predicted by in silico analyses were experimentally verified in-vitro and in-vivo. RESULTS: Baicalin significantly inhibited proliferation, invasion, migration, and induced apoptosis in MC38 and CT26 cells (all P<0.01). Additionally, baicalin caused cell cycle arrest at the S phase, while the G0/G1 phase was detected in the tiny portion of the cells. Subsequent network pharmacology analysis identified 6 therapeutic targets associated with baicalin, which potentially affect various pathways including 39 biological processes and 99 signaling pathways. In addition, molecular docking and DARTS predicted the potential binding of baicalin with cyclin dependent kinase inhibitor 2A (CDKN2A), protein kinase B (AKT), caspase 3, and mitogen-activated protein kinase (MAPK). In vitro, the expressions of CDKN2A, MAPK, and p-AKT were suppressed by baicalin in MC38 and CT26 cells. In vivo, baicalin significantly reduced the tumor size and weight (all P<0.01) in the colon cancer mouse model via inactivating p-AKT, CDKN2A, cyclin dependent kinase 4, cyclin dependent kinase 2, interleukin-1, tumor necrosis factor α, and activating caspase 3 and mouse double minute 2 homolog signaling (all P<0.05). CONCLUSION: Baicalin suppressed the CDKN2A protein level to prevent colon cancer and could be used as a therapeutic target for colon cancer.

18.
Chempluschem ; 88(5): e202300002, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36754829

RESUMO

In this study, Cu-SSZ-13 zeolites are successfully coated with mesoporous metal oxides (CeO2 , Fe2 O3 , TiO2 and SiO2 ) and prepared as core-shell Cu-SSZ-13@meso-MOx samples with hierarchical pore structure. Compared with Cu-SSZ-13, the catalytic activity and hydrothermal stability of the Cu-SSZ-13@meso-MOx have been greatly improved. The promoting effect of meso-MOx shell on the catalytic activity of Cu-SSZ-13 is mainly attribute to the presence of both microporous and mesoporous structures, the formation of more active isolated Cu2+ ions and more L-acid sites, and the synergistic effect between Cu-SSZ-13 and meso-MOx interaction. Moreover, all the Cu-SSZ-13@meso-MOx catalysts maintain their activities to a greater extent after hydrothermal aging. The core-shell structure may play a protective role and greatly improve the hydrothermal stability of Cu-SSZ-13. More L-acidic sites and more isolated Cu2+ ions are preserved under the protection of mesoporous structure.

19.
Exp Ther Med ; 26(3): 439, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37614427

RESUMO

Breast cancer (BC) is a life-threatening malignant tumor that affects females more commonly than males. The mechanisms underlying BC proliferation, metastasis and glycolysis require further investigation. Homeobox C13 (HOXC13) is highly expressed in BC; however, the specific mechanisms in BC are yet to be fully elucidated. Therefore, the aim of the present study was to investigate the role of HOXC13 in BC proliferation, migration, invasion and glycolysis. In the present study, the UALCAN database was used to predict the expression levels of HOXC13 in patients with BC. Western blot analysis and reverse transcription-quantitative PCR were used to determine the expression levels of HOXC13 in BC cell lines. Moreover, HOXC13 knockdown was induced using cell transfection, and the viability, proliferation and apoptosis of cells were detected using Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine staining and flow cytometry. Migration, invasion and epithelial-mesenchymal transition (EMT) were measured using wound healing assay, Transwell assay and western blotting. In addition, XF96 extracellular flux analyzer and corresponding kits were used to detect glycolysis. The JASPAR database was used to predict promoter binding sites for the transcription factors HOXC13 and DNA methyltransferase 3α (DNMT3A). HOXC13 expression was silenced and DNMT3A was simultaneously overexpressed using cell transfection. The results of the present study revealed that HOXC13 expression was significantly elevated in BC tissues and cells. Following HOXC13 knockdown in BC cells, the viability, proliferation, glycolysis, migration, invasion and EMT were significantly decreased, and apoptosis was significantly increased. In addition, HOXC13 positively regulated the transcription of DNMT3A in BC cells, thus playing a regulatory role in the malignant progression of cells. In conclusion, HOXC13 promoted cell viability, proliferation, migration, invasion, EMT and glycolysis in BC by regulating DNMT3A.

20.
Adv Sci (Weinh) ; 10(3): e2205054, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36437038

RESUMO

Chlorinated volatile organic compounds (CVOCs) are a class of hazardous pollutants that severely threaten environmental safety and human health. Although the catalytic oxidation technique for CVOCs elimination is effective, enhancing the catalytic efficiency and simultaneously inhibiting the production of organic byproducts is still of great challenge. Herein, Ru-substituted LaMn(Ru)O3+ δ perovskite with Ru-O-Mn structure and weakened Mn-O bond strength has been developed for catalytic oxidation of chlorobenzene (CB). The formed Ru-O-Mn structure serves as favorable sites for CB adsorption and activation, while the weakening of Mn-O bond strength facilitates the formation of active oxygen species and improves oxygen mobility and catalyst reducibility. Therefore, LaMn(Ru)O3+ δ exhibits superior low-temperature activity with the temperature of 90% CB conversion decreasing by over 90 °C compared with pristine perovskite, and the deep oxidation of chlorinated byproducts produced in low temperature is also accelerated. Furthermore, the introduction of water vapor into reaction system triggers the process of hydrolysis oxidation that promotes CB destruction and inhibits the generation of chlorinated byproducts, due to the higher-activity *OOH species generated from the dissociated H2 O reacting with adsorbed oxygen. This work can provide a unique, high-efficiency, and facile strategy for CVOCs degradation and environmental improvement.

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