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1.
J Org Chem ; 89(7): 4530-4537, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38483270

RESUMO

A copper-catalyzed method for the dehydrogenation of various nitrogen-containing heterocycles to furnish quinolines and indoles has been developed. A range of 1,2,3,4-tetrahydroquinolines underwent dehydrogenation by employing 2 mol % of copper complex Cat 3 as a catalyst and using O2 as an oxidant at 120 °C in 1,2-dichlorobenzene to afford the desired quinolines. The method enables the dehydrogenation of a variety of indolines in the presence of 2 mol % of copper complex Cat 2, using 10 mol % of TEMPO as an additive and O2 as an oxidant under room temperature in tetrahydrofuran to furnish indoles in high yields. Mechanistic studies suggested that the dehydrogenative activity is ascribed to the formation of a copper(II) active species from copper(I) complexes oxidized by O2, which was proved by high-resolution mass spectrometry (HRMS). The copper-catalyzed dehydrogenation reaction proceeds via a superoxide radical anion (·O2-) as proved by electron paramagnetic resonance (EPR) spectrometry. In situ infrared spectroscopy revealed that the dihydroquinoline intermediate was formed in the dehydrogenation of 1,2,3,4-tetrahydroquinolines.

2.
Small ; 19(33): e2301497, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37086131

RESUMO

Chemodynamic therapy (CDT) relies on the tumor microenvironment (e.g., high H2 O2 level) responsive Fenton-like reactions to produce hydroxyl radicals (·OH) against tumors. However, endogenous H2 O2 is insufficient for effective chemodynamic responses. An NAD(P)H: quinone oxidoreductase 1 (NQO1)high catalase (CAT)low therapeutic window for the use of NQO1 bioactive drug ß-lapachone (ß-Lap) is first identified in endometrial cancer (EC). Accompanied by NADH depletion, NQO1 catalyzes ß-Lap to produce excess H2 O2 and initiate oxidative stress, which selectively suppress NQO1high EC cell proliferation, induce DNA double-strand breaks, and promote apoptosis. Moreover, shRNA-mediated NQO1 knockdown or dicoumarol rescues NQO1high EC cells from ß-Lap-induced cytotoxicity. Arginine-glycine-aspartic acid (RGD)-functionalized iron-based metal-organic frameworks (MOF(Fe)) further promote the conversion of the accumulated H2 O2 into highly oxidative ·OH, which in turn, exacerbates the oxidative damage to RGD-positive target cells. Furthermore, mitophagy inhibition by Mdivi-1 blocks a powerful antioxidant defense approach, ultimately ensuring the anti-tumor efficacy of stepwise-amplified reactive oxygen species signals. The tumor growth inhibition rate (TGI) is about 85.92%. However, the TGI of MOF(Fe)-based synergistic antitumor therapy decreases to only 50.46% in NQO1-deficient KLE tumors. Tumor-specific chemotherapy and CDT-triggered therapeutic modality present unprecedented therapeutic benefits in treating NQO1high EC.


Assuntos
Neoplasias do Endométrio , Mitofagia , Humanos , Feminino , Apoptose , Oligopeptídeos , Linhagem Celular Tumoral , Microambiente Tumoral
3.
Langmuir ; 39(49): 18022-18030, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38029304

RESUMO

Olefins can be cracked to provide more low-carbon olefins than paraffins; therefore, separation of olefin/paraffin mixtures is essential for arranging hydrocarbon molecules for directed conversion. In this article, a simple approach for reducing copper atoms in Cu-BTC has been developed to improve olefin/paraffin adsorption capacity and selectivity. Considering that Cu-BTC shows adsorption benefits, its olefin/paraffin adsorption and separation performance were improved further by in situ reduction of Cu(II) to Cu(I) in Cu-BTC using ethanol as the reducing agent and nickel ions as the catalyst. The results revealed that during the reduction process, Cu ion conversion from tetra-ligand to diligand considerably increased their specific surface area, resulting in more active adsorption sites inside the modified sample. The ratio of Cu(I)/Cu(II) in the modified samples varied from 0.57 to 0.96. When Cu(II) of Cu-BTC was reduced to Cu(I), the adsorption capacities of 1-hexene increased from 145.97 to 243.65 mg/g, whereas n-hexane adsorption increased only slightly from 8.18 to 11.43 mg/g, resulting in an acceptable increase in selectivity from 17.84 to 21.32. Cu-BTC, due to its own Cu atoms, minimizes the substantial requirements for the synthesis process as well as the oxygen avoidance conditions for storage when monovalent copper is introduced, compared to other porous materials. Experimental results found that when Cu(I) was introduced, the Lewis acidic sites of the modified Cu-BTC material were increased, and Cu(I) has an electrical structure that makes it susceptible to both accepting and donating too many d electrons, resulting in a stronger adsorption of olefins containing π-electrons to them. Materials Studio simulation revealed that the isosteric heats of modified Cu-BTC increased by 2.7 kJ/mol, indicating that it has a stronger adsorption capacity for olefins.

4.
J Org Chem ; 88(22): 15717-15725, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37885137

RESUMO

A binary catalytic system comprising tetrahydroxydiboron and tetrabutylammonium iodide (TBAI) was used to catalyze the cycloaddition of carbon dioxide (CO2) with epoxides. The tetrahydroxydiboron catalyst (9 mol %), in combination with the use of TBAI (13.5 mol %) as a nucleophile, is capable of catalyzing the cycloaddition of CO2 with various terminal epoxides under room temperature and a CO2 balloon. In addition, a range of internal epoxides, including sterically hindered bicyclic epoxides and vegetable oil-based epoxides, were suitable for the catalytic system, affording a series of cyclic carbonates in moderate to high yields. The tetrahydroxydiboron/TBAI cooperative catalytic mechanism was elucidated using Fourier transform infrared spectroscopy, nuclear magnetic resonance, and electrospray ionization-high-resolution mass spectrometry. Results reveal that the tetrahydroxydiboron catalyst exhibits dual effects, activating both CO2 and epoxides; initially, it underwent the insertion of CO2 to form a boron-CO2 adduct and subsequently activated the epoxides through interaction of the B-O bond.

5.
J Nanobiotechnology ; 21(1): 17, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647107

RESUMO

BACKGROUND: Superhydrophobic substrate modifications are an effective way to improve SERS sensitivity by concentrating analyte molecules into a small surface area. However, it is difficult to manipulate low-volume liquid droplets on superhydrophobic substrates. RESULTS: To overcome this limitation, we deposited a hydrophilic Ti3C2Tx film on a superhydrophobic ZnO nanorod array to create a SERS substrate with improved analyte affinity. Combined with its interfacial charge transfer properties, this enabled a rhodamine 6G detection limit of 10-11 M to be achieved. In addition, the new SERS substrate showed potential for detection of biological macromolecules, such as microRNA. CONCLUSION: Combined with its facile preparation, the SERS activity of ZnO/Ti3C2Tx suggests it may provide an ultrasensitive environmental pollutant-monitoring and effective substrate for biological analyte detection.


Assuntos
Poluentes Ambientais , Óxido de Zinco , Óxido de Zinco/química , Análise Espectral Raman , Titânio/química , Prata/química , Interações Hidrofóbicas e Hidrofílicas , Poluentes Ambientais/análise
6.
Anim Biotechnol ; 34(7): 2094-2105, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35622393

RESUMO

Reproductive traits have a high economic value in goat breeding, and increasing the number of lambs produced by ewes is of great importance to improve the production efficiency of goat farming. Lambing traits in goats are low heritability traits, but their genetic basis is ultimately determined by genes. This study aimed to investigate the relationship between INHA, RARG, and PGR gene polymorphisms and production performance, such as lambing, cashmere production, milk production, and body size in Liaoning cashmere goats. A total of six single nucleotide polymorphisms (SNPs) loci were identified in these three genes, G144A and T504C on the INHA gene, A56G, G144A, G490C on the RARG gene, and G109519T on the PGR gene. For lambing and cashmere production traits, the AA genotype of G144A on the INHA gene, TT on the T504C genotype, GG genotype of G144A on the INHA gene, A56G, G144A, and T504C on RARG and G109519T on PGR gene are dominant genotypes. AATT is a dominant haplotype combination. Allele G can be used as a molecular marker for lambing, cashmere, and milk production traits in Liaoning cashmere goats. Marker-assisted selection can be used for early selection to achieve improvement of genetic traits in Liaoning cashmere goats.


Assuntos
Cabras , Polimorfismo de Nucleotídeo Único , Ovinos/genética , Animais , Feminino , Cabras/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Genótipo , Carneiro Doméstico , Reprodução/genética
7.
Langmuir ; 38(5): 1869-1876, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35080891

RESUMO

Nanosized gold nanoparticles (AuNPs) are of great interest in areas such as catalysts or imaging but are easy to aggregate due to high surface activity. To stabilize AuNPs, two approaches were employed to immobilize AuNPs in spherical polymer brushes (SPBs), namely, the in situ preparation of AuNPs within the brush layer of SPBs and external addition of preprepared citrate-capped AuNPs. The distribution and stability of AuNPs in SPBs were studied by small-angle X-ray scattering (SAXS). SAXS results demonstrated that the in situ-prepared AuNPs were mainly located on the inner layer and their amount decreased from inside to outside. In the case of external addition of preprepared AuNPs, the cationic SPB showed obvious immobilization, while almost no AuNPs were immobilized in the anionic SPB. The stable immobilization of the AuNPs in SPBs was the result of multiple interactions including complexation and electrostatic interaction. SAXS was validated to be a distinctive and powerful characterization method to provide theoretical guidance for the stable immobilization of AuNPs.


Assuntos
Ouro , Nanopartículas Metálicas , Polímeros , Espalhamento a Baixo Ângulo , Difração de Raios X , Raios X
8.
J Surg Res ; 279: 338-351, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35810551

RESUMO

INTRODUCTION: The rarity of primary pulmonary synovial sarcoma (PPSS) and the lack of prospective clinical trials resulted in poorly understood treatment modality and clinical outcomes. This study aimed to better understand PPSS based on patients from the Surveillance, Epidemiology, and End Results database. MATERIALS AND METHODS: Clinical and survival data of PPSS patients who were diagnosed during 1989 through 2016 and retrieved from the Surveillance, Epidemiology, and End Results database were studied. Kaplan-Meier analyses and Cox proportional hazards model were applied to evaluate the overall survival (OS) and disease-specific survival (DSS) of PPSS patients. RESULTS: A total of 122 patients with PPSS were included (median age: 50 y). PPSS accounted for 4.5% (122/2741) of total primary synovial sarcoma. Most of the patients were diagnosed as poor or undifferentiated grade (52.0% and 34.0%). Cancer-directed surgery was performed for 74.4% of PPSS patients and 28.2% of patients received radiotherapy. The 1-year, 3-year, 5-year, and 10-year OS rates of PPSS patients were 75.4%, 50.8%, 41.8%, and 39.3%, respectively. Cancer-directed surgery was shown to improve the survival of PPSS patients with localized or regional stage (P < 0.05), yet surgical resection did not prolong the OS and DSS of patients with distant stage (P > 0.1). Postoperational radiotherapy was associated with shortened survival time (P < 0.05). PPSS patients who received lobectomy had statistically prolonged OS and DSS than those with pneumonectomy (P < 0.001). CONCLUSIONS: PPSS is a rare and special subtype of synovial sarcoma. Treatment with lobectomy or sublobar resection alone may contribute to a superior prognosis compared with other managements.


Assuntos
Neoplasias Pulmonares , Sarcoma Sinovial , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/cirurgia , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Programa de SEER , Sarcoma Sinovial/cirurgia
9.
Org Biomol Chem ; 20(4): 847-851, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34994375

RESUMO

An efficient Pd-catalyzed direct C-H arylation of pyrrolo[1,2-a]quinoxalines with aryl iodides is described, providing a selective route toward a series of 1-arylated and 1,3-diarylated pyrrolo[1,2-a]quinoxalines in good yields. This method features a broad substrate scope, good functional group tolerance and gram-scale synthesis. Furthermore, the C3-thiocyanation of the arylated product is also achieved. We believe that these novel aryl-substituted pyrrolo [1,2-a]quinoxalines will have a variety of applications in organic synthesis and medicinal chemistry.

10.
BMC Cancer ; 21(1): 148, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568091

RESUMO

BACKGROUND: Lung cancer remains the leading cause of cancer death globally. In 2015, the cancer classification guidelines of the World Health Organization were updated. The term "invasive mucinous adenocarcinoma (IMA)" aroused people's attention, while the clinicopathological factors that may influence survival were unclear. METHODS: Data of IMA patients was downloaded from SEER database. Kaplan-Meier methods and log-rank tests were used to compare the differences in OS and LCSS. The nomogram was developed based on the result of the multivariable analysis. The discrimination and accuracy were tested by Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analyses (DCA). Integrated discrimination improvement (IDI) index was used to evaluate the clinical efficacy. RESULTS: According to multivariate analysis, the prognosis of IMAs was associated with age, differentiation grade, TNM stage and treatments. Surgery might be the only way that would improve survival. Area under the curve (AUC) of the training cohort was 0.834and 0.830 for3-and 5-year OS, respectively. AUC for 3-and 5-year LCSS were separately 0.839 and 0.839. The new model was then evaluated by calibration curve, DCA and IDI index. CONCLUSION: Based on this study, prognosis of IMAs was systematically reviewed, and a new nomogram was developed and validated. This model helps us understand IMA in depth and provides new ideas for IMA treatment.


Assuntos
Adenocarcinoma Mucinoso/mortalidade , Bases de Dados Factuais/estatística & dados numéricos , Neoplasias Pulmonares/mortalidade , Nomogramas , Programa de SEER , Adenocarcinoma Mucinoso/epidemiologia , Adenocarcinoma Mucinoso/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Curva ROC , Estudos Retrospectivos , Taxa de Sobrevida , Revisões Sistemáticas como Assunto , Estados Unidos/epidemiologia
11.
Angew Chem Int Ed Engl ; 60(25): 13959-13968, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-33844380

RESUMO

Controlling crystal size and shape of zeolitic materials is an effective way to promote their mass transport and catalytic properties. Herein, we report a single step, Na+ - and porogen- free crystallization of MFI hierarchical architecture made up of aligned nanocrystals with reduced b-axis thickness (5-23 nm) and adjustable Si/Al ratios between 35 to 120, employing the commonly used tetrapropylammonium hydroxide (TPAOH) and tetrabutylammonium hydroxide (TBAOH) as structure-directing agents (SDAs). Homogeneous nucleation driven by both SDAs and subsequent SDA-exchange induced dissolution-recrystallization are responsible for the formation of such structure. The enhanced textural and diffusion properties account for a notable exaggeration of propene selectivity and catalyst lifetime in dimethyl ether-to-olefins (DTO) conversion. This protocol is extendable to the rational synthesis of other hierarchical zeolites through crystallization process control.

12.
J Transl Med ; 18(1): 237, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539859

RESUMO

BACKGROUND: Survival outcomes of patients with resected SCLC differ widely. The aim of our study was to build a model for individualized risk assessment and accurate prediction of overall survival (OS) in resectable SCLC patients. METHODS: We collected 1052 patients with resected SCLC from the Surveillance, Epidemiology, and End Results (SEER) database. Independent prognostic factors were selected by COX regression analyses, based on which a nomogram was constructed by R code. External validation were performed in 114 patients from Shandong Provincial Hospital. We conducted comparison between the new model and the AJCC staging system. Kaplan-Meier survival analyses were applied to test the application of the risk stratification system. RESULTS: Sex, age, T stage, N stage, LNR, surgery and chemotherapy were identified to be independent predictors of OS, according which a nomogram was built. Concordance index (C-index) of the training cohort were 0.721, 0.708, 0.726 for 1-, 3- and 5-year OS, respectively. And that in the validation cohort were 0.819, 0.656, 0.708, respectively. Calibration curves also showed great prediction accuracy. In comparison with 8th AJCC staging system, improved net benefits in decision curve analyses (DCA) and evaluated integrated discrimination improvement (IDI) were obtained. The risk stratification system can significantly distinguish the ones with different survival risk. We implemented the nomogram in a user-friendly webserver. CONCLUSIONS: We built a novel nomogram and risk stratification system integrating clinicopathological characteristics and surgical procedure for resectable SCLC. The model showed superior prediction ability for resectable SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Estudos de Coortes , Humanos , Nomogramas , Prognóstico
13.
Langmuir ; 34(4): 1340-1346, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29293350

RESUMO

The quality of nanoparticle dispersion in a polymer matrix significantly influences the macroscopic properties of the composite material. Like general polymer-nanoparticle composites, electrospun nanofiber nanoparticle composites do not have an adopted quantitative model for dispersion throughout the polymer matrix, often relying on a qualitative assessment. Being such an influential property, quantifying dispersion is essential for the process of optimization and understanding the factors influencing dispersion. Here, a simulation model was developed to quantify the effects of nanoparticle volume loading (ϕ) and fiber-to-particle diameter ratios (D/d) on the dispersion in an electrospun nanofiber based on the interparticle distance. A dispersion factor is defined to quantify the dispersion along the polymer fiber. In the dilute regime (ϕ < 20%), three distinct regions of the dispersion factor were defined with the highest quality dispersion shown to occur when geometric constraints limit fiber volume accessibility. This model serves as a standard for comparison for future experimental studies and dispersion models through its comparability with microscopy techniques and as a way to quantify and predict dispersion in electrospinning polymer-nanoparticle systems with a single performance metric.

14.
ChemSusChem ; 17(1): e202301015, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37661194

RESUMO

Synthesizing benzyl skeleton derivatives via direct oxidation of functionalized benzylic C-H bonds has received extensive research attention. Herein, a method was developed to prepare carbonyl compounds via photoinduced aerobic oxidation of ubiquitous benzylic C-H bonds mediated by bromine radicals and tribromomethane radicals. This method employed commercially available CBr4 as a hydrogen atom transfer reagent precursor, air as an oxidant, water as a reaction solvent, and tetrabutylammonium perchlorate (TBAPC) as an additive under mild conditions. A series of substrates bearing different functional groups was converted to aromatic carbonyls in moderate to good yields. Moreover, a low environmental factor (E-factor value=0.45) showed that the proposed method is ecofriendly and environmentally sustainable.

15.
Chem Biol Interact ; 387: 110794, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37951334

RESUMO

Ferroptosis is an iron-dependent cell death and affects efficacies of multiple antitumor regimens, showing a great potential in cancer therapy. Protein kinase D2 (PKD2) plays a crucial role in regulating necrosis and apoptosis. However, the relationship of PKD2 and ferroptosis is still elusive. In this study, we mainly analyzed the roles of PKD2 on ferroptosis and chemotherapy in lung adenocarcinoma (LUAD). We found PKD2 was highly expressed in LUAD and silencing PKD2 could promote erastin-induced reactive oxygen species (ROS), malondialdehyde (MDA) accumulation, intracellular iron content and LUAD cells death. Mechanistically, augmenting PKD2 could prevent autophagic degradation of ferritin, which could be impaired by bafilomycin A1. We further found that PKD2 overexpression would promote LC3B-II, p62/SQSTM1 accumulation and block autophagosome-lysosome fusion in a TFEB-independent manner, which could be impaired by bafilomycin A1. Bafilomycin A1 stimulation could weaken ferroptosis promotion by PKD2 abrogation. Silencing ferritin heavy chain-1 (FTH1) could reverse the resistance to ferroptosis by PKD2 overexpression. Additionally, in vitro and vivo experiments validated PKD2 promoted proliferation, migration and invasion of LUAD cells. PKD2 knockdown or pharmacological inhibition by CRT0066101 could enhance efficacy of carboplatin in LUAD via ferroptosis and apoptosis. Collectively, our study revealed that abrogation of PKD2 could aggravate ferritinophagy-mediated ferroptosis by promoting autophagosome-lysosome fusion and enhance efficacy of carboplatin in LUAD. Targeting PKD2 to induce ferroptosis may be a promising strategy for LUAD therapy.


Assuntos
Adenocarcinoma de Pulmão , Carboplatina , Ferroptose , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Autofagossomos/metabolismo , Autofagia , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Ferro/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Lisossomos/metabolismo , Proteína Quinase D2 , Proteínas Serina-Treonina Quinases/metabolismo
16.
Org Lett ; 26(17): 3487-3492, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38634857

RESUMO

A novel type of highly efficient chiral C2-symmetric bipyridine-N,N'-dioxides ligand application in catalyzing Michael addition/Cyclization of 5-aminopyrazoles with α,ß-unsaturated 2-acyl imidazoles has been developed, affording the corresponding adducts in 85-97% yield with up to 99% enantioselectivity under mild conditions with a lower catalyst loading and broad scope. Remarkably, this protocol exhibits advantages in terms of reactivity and enantioselectivity, giving the fact that as low as 2.2 mol % of L1 and 2.0 mol % of Ni(OTf)2 can promote the title reaction on gram scale to afford the desired product with excellent enantioselectivity.

17.
J Colloid Interface Sci ; 662: 479-489, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364473

RESUMO

The introduction of heteroatoms into hollow carbon spheres is imperative for enhancing catalytic activity. Consequently, we investigated the utilization of nitrogen-oxygen(N/O) co-doped hollow carbon (C)/silica (SiO2) nanospheres (NxC@mSiO2), which have a large internal volume and a nano-constrained environment that limits metal aggregation and loss, making them a potential candidate. In this study, we demonstrate the synthesis of nitrogen-oxygen (N/O) co-doped hollow carbon spheres using resorcinol and formaldehyde as carbon precursors, covered with silica, and encapsulated with palladium nanoparticles (NPs) in situ. The N/O co-doping process introduced defects on the surface of the internal C structure, which acted as active sites and facilitated substrate adsorption. Subsequent treatment with hydrogen peroxide (H2O2) introduced numerous carboxyl groups onto the C structure, increasing the catalytic environment as acid auxiliaries. The carboxyl group is present in the carbon structure, as determined calculations based on by density functional theory, reduces the adsorption energy of acetylene, thereby promoting its adsorption and enrichment. Furthermore, H2O2-treatment enhanced the oxygen defects in the carbon structure, improving the dispersion of Pd NPs and defect structure. The Pd/NxC@mSiO2-H2O2 catalysts demonstrated outstanding performance in the acetylene dialkoxycarbonylation reaction, showcasing high selectivity towards 1,4-dicarboxylate (>93 %) and remarkable acetylene conversion (>92 %). Notably, the catalyst exhibited exceptional selectivity and durability throughout the reaction.

18.
Macromol Biosci ; : e2300528, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444237

RESUMO

Hydrogel wound dressing can accelerate angiogenesis to achieve rapid wound healing, but traditional hydrogel dressings are difficult to meet the repair of joint sites due to their low mechanical strength. Therefore, we constructed the gel system by designing the chemical-physical interpenetrating network structure to achieve high strength and high toughness of the hydrogel. The high-strength double-network hydrogels were synthesized by simple free radical polymerization and low-temperature physicochemical cross-linking in our experiments. The suspension was obtained by green reduction of graphene oxide with carboxymethyl chitosan, followed by the introduction of acrylamide (AM) to form a covalent cross-linked network, which was immersed in ferric chloride solution to form metal ligand bonds, and finally the chemical-physical dual cross-linked network hydrogel wound dressing was prepared. Here, reduced graphene oxide can enhance electrical conductivity and excellent near-infrared photothermal effect to the hydrogel. The cell viability of this novel wound dressing was above 90.0%, its hemolysis rate was below 2.0%, and the electrical conductivity could reach (6.89 ± 0.07 (mS/cm)). In addition, the stress-strain curve demonstrated that the double cross-linked network hydrogel could reach a stress of more than 0.8 MPa at 82.0% strain, and the cyclic compression experiment shows that it can still recover its original shape after five times of repeated compression. This work can provide a reference for the exploitation of high mechanical strength hydrogel wound dressings with good electrical conductivity and near-infrared photothermal effect. This article is protected by copyright. All rights reserved.

19.
ChemSusChem ; 17(6): e202301538, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38376216

RESUMO

Construction of S-scheme heterojunction offers a promising way to enhance the photocatalytic performance of photocatalysts for converting solar energy into chemical energy. However, the photocatalytic H2 production in pure water without sacrificial agents is still a challenge. Herein, the IEF-11 with the best photocatalytic H2 production performance in MOFs and suitable band structure was selected and firstly constructed with g-C3N4 to obtain a S-scheme heterojunction for photocatalytic H2 production from pure water. As a result, the novel IEF-11/g-C3N4 heterojunction photocatalysts exhibited significantly improved photocatalytic H2 production performance in pure water without any sacrificial agent, with a rate of 576 µmol/g/h, which is about 8 times than that of g-C3N4 and 23 times of IEF-11. The novel IEF-11/g-C3N4 photocatalysts also had a photocatalytic H2 production rate of up to 92 µmol/g/h under visible light and a good photocatalytic stability. The improved performance can be attributed to the efficient separation of photogenerated charge carriers, faster charge transfer efficiency and longer photogenerated carrier lifetimes, which comes from the forming of S-scheme heterojunction in the IEF-11/g-C3N4 photocatalyst. This work is a promising guideline for obtaining MOF-based or g-C3N4-based photocatalysts with great photocatalytic water splitting performance.

20.
iScience ; 26(10): 108055, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37854704

RESUMO

Small nucleolar RNA host genes (SNHGs) are a special family of long non-coding RNAs (lncRNAs), which not only function in a way similar to other lncRNAs but also influence the intracellular level of small nucleolar RNAs to modulate cancers. However, the features of SNHGs and their role in the prognosis and immunotherapeutic response of human cancer have not been explored. We found that SNHGs were commonly deregulated and correlated with patient survival in various cancers. The critical role of DNA methylation and somatic alterations on deregulation was also identified. SNHG family score was significantly associated with survival, multiple tumor characteristics, and tumor microenvironment. SNHG-related risk score could serve as a prognostic and immunotherapeutic response biomarker based on multiple databases. This study emphasizes the potential of SNHGs as biomarkers for prognosis and immunotherapeutic response, enabling further research into the immune regulatory mechanism and therapeutic potentials of SNHGs in cancer.

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