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1.
Chemistry ; : e202402699, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354575

RESUMO

Cyclic carbonate hydrogenation offers an alternative for the efficient indirect CO2 utilization. In this study, a series of carbon nanotubes (CNTs) supported xCu/CNTs catalysts with different Cu loadings were fabricated using a convenient impregnation method, and exhibited excellent catalytic activity for the hydrogenation of ethylene carbonate to methanol and ethylene glycol. The structural and physicochemical properties revealed that acid treatment of CNTs resulted in plentiful oxygen-containing functional groups, providing sufficient anchoring sites for copper species. The calcination process conducted under an inert atmosphere resulted in the formation of ternary CuO, Cu2O, and Cu composites, enhancing the metal-support interaction and facilitating the formation of balanced Cu0 and Cu+ dual sites as well as high active surface area after reduction. Contributed to the synergetic effect of balanced Cu+ and Cu0 species proved by density functional theory calculation and the electron-rich CNTs surface, the 40Cu/CNTs catalyst achieved strengthened catalytic performance with methanol yield of 83%, ethylene glycol yield of 99% at ethylene carbonate conversion of >99%, and 150 h of long-term running stability. Consequently, CNTs supported Cu serve as efficient non-silica based catalyst for ester hydrogenation.

2.
Angew Chem Int Ed Engl ; : e202415203, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39263728

RESUMO

Developing an efficient strategy to replace the conventional synthesis method for producing isoindolinone (IIO) scaffold, a crucial structural motif for constructing pharmaceutical molecules, remains to be a great challenge. Herein, a single-atom Pd/TiO2 tandem catalysis has been developed for the IIO scaffold synthesis by using readily available phthalic anhydride (PA), ammonia, and H2. The single-atom Pd/TiO2 catalyst demonstrates superior catalytic performance, achieving a PA conversion of 99%, an IIO selectivity of 91%, and a turnover frequency (TOF) up to 4807 h-1. This exceptional performance can be attributed to the tandem catalysis between TiO2 support and single-atom Pd. The TiO2 efficiently catalyzes the conversion of PA with ammonia to form phthalimide (PAM), subsequently transformed into IIO over TiO2 through the reaction of PAM with NH3 and the spillover hydrogen species derived from single-atom Pd. Notably, NH3 functions not only as a reactant but also as a promoter to accelerate the reduction of amides combined with the Pd/TiO2 catalyst. This tandem catalysis of a single-atom Pd/TiO2 catalyst provides a promising strategy for the synthesis of the crucial IIO platform molecules.

3.
ACS Appl Mater Interfaces ; 16(39): 52572-52582, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39303292

RESUMO

With the increasing demand for energy and worsening environmental issues, the application of photothermal materials has been widely explored due to their high energy conversion capabilities and environmental friendliness. In this work, metal-carbon fiber composites were prepared and subjected to photothermal and water evaporation performance tests alongside pure metals and pyrolytic phenolic resin materials. The results show that the addition of metals effectively improved the photothermal efficiency by narrowing the molecular energy gaps of the materials, indicating a strong synergistic enhancement effect between metals and carbon materials. This study provides a theoretical basis for the design of high-performance photothermal conversion materials.

4.
Environ Sci Pollut Res Int ; 31(44): 56091-56113, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39251537

RESUMO

This study focused on investigating thermal degradation behaviors, kinetics, reaction mechanisms, synergistic effects, and thermodynamic parameters of wood sawdust (WSD), linear low-density polyethylene (LLDPE), and their blends (LW1:3, LW1:1, and LW3:1) during co-pyrolysis in a thermogravimetric analyzer (TGA). Thermal behavior exhibited a LW1:3 blend (25 wt.% LLDPE) showing significant mass loss at lower temperatures (150 to 300 °C) compared to the individual feedstocks, such as 150 to 400 °C and 300 to 520 °C for WSD and LLDPE, respectively. The iso-conversional methods (KAS, FWO, and FM) were used to determine the kinetic parameters (Ea and A), and the activation energy drop was highest for the LW1:3 blend. According to the master plots, the third-order reaction (O3), nucleation (P2/3), and diffusional model (D4) were the predominant reaction mechanisms for the co-pyrolysis of the LW1:3, LW1:1, and LW3:1 blend, respectively. The thermodynamic parameters demonstrate that a small amount of plastic addition into WSD can improve the reactivity of the blend, shorten the reaction time, and cause less energy-intensive reactions. The values of ΔH, ΔG, and ΔS also confirmed the co-pyrolysis process's spontaneity and endothermic nature. The Fourier transforms infrared spectrometer (FTIR) spectra of raw feedstock, blends, and their biochar revealed some of the peaks were shifted, the intensity was reduced, and disappearance can happen when the temperature was increased. Using the experimental and theoretical/predicted activation energies, the parity chart illustrates the synergistic effects of co-pyrolysis of different blends, and the LW1:3 blend has a favorable synergistic impact. These results could be helpful in process optimization and designing an effective reactor system for co-pyrolysis.


Assuntos
Polietileno , Pirólise , Termodinâmica , Termogravimetria , Madeira , Madeira/química , Cinética , Polietileno/química
5.
ChemSusChem ; : e202401362, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162037

RESUMO

The photocatalytic cycloaddition reaction between CO2 and epoxide is one of the most promising green routes for CO2 utilization, for which high performance photocatalysts are intensely desired. Herein, we have constructed an S-scheme heterojunction of MIL-125@ZIF-67 modified by amino groups, which achieves a cyclic carbonate yield of as high as 99% without employing any co-catalyst, outperforming the previously reported photocatalysts. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and in-situ electron paramagnetic resonance (EPR) spectroscopy reveal the important role of photogenerated electron migration from Lewis acid (Co) sites to the O atom of epoxide in triggering its ring-opening (the rate-determining step of CO2 cycloaddition reaction) under the assistance of photogenerated hole. Synergistically and concurrently, the Lewis base (amino groups) sites activate CO2 to CO2*, facilitating the following CO2 cycloaddition. Such a synergistic effect provides a most favorable approach to design efficient heterogeneous photocatalysts with dual/multiple-active sites for CO2 cycloaddition reaction.

7.
Eur J Med Chem ; 276: 116724, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39079310

RESUMO

For the first time, a synthetic route for preparing lupane and oleanane derivatives with a hydrogenated furan ring as a cycle A of triterpene scaffold is described. Most of the synthesized compounds, furanoterpenoids and their synthetic intermediates, were non-toxic against the tested cancer and non-cancerous cell lines, and evinced significant inhibitory activity with IC50 1.0-9.0 µM in the tyrosyl-DNA phosphodiesterase 1 (Tdp1) inhibition test. Lupane derivatives - 1-oxime 7, 1,10-seco-hydroxynitrile 11 and furanoterpenoid 14 - were selected as those expected to be the most promising compounds. The results of molecular modeling evinced the strongest binding of compound 11 to the active site of Tdp1 compared to the reference drug. Simultaneously, only compound 11 at subtoxic concentration (10 µM) produced a synergetic effect on the topotecan activity against HeLa-V cells.


Assuntos
Relação Dose-Resposta a Droga , Inibidores de Fosfodiesterase , Diester Fosfórico Hidrolases , Triterpenos , Humanos , Diester Fosfórico Hidrolases/metabolismo , Relação Estrutura-Atividade , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/síntese química , Inibidores de Fosfodiesterase/farmacologia , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/química , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/farmacologia , Furanos/química , Furanos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Modelos Moleculares , Linhagem Celular Tumoral , Ácido Betulínico
8.
J Colloid Interface Sci ; 673: 9-18, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38870666

RESUMO

Hydrogen peroxide (H2O2) emerges as a viable oxidant for fuel cells, necessitating the development of an efficient and cost-effective electrocatalyst for the hydrogen peroxide reduction reaction (HPRR). In this study, we synthesized a self-supporting, highly active HPRR electrocatalyst comprising two morphologically distinct components: CeO2-NiCo2O4 nanowires and CeO2-NiCo2O4 metal organic framework derivatives, via a two-step hydrothermal process followed by air calcination. X-ray diffraction and transmission electron microscopy analysis confirmed the presence of CeO2 and NiCo2O4, revealing the amalgamated interface between them. CeO2 exhibits multifunctionality in regulating the surface electronic configuration of NiCo2O4, fostering synergistic connections, and introducing oxygen deficiencies to enhance the catalytic efficacy in HPRR. Electrochemical measurements demonstrate a reduction current density of 789.9 mA·cm-2 at -0.8 V vs. Ag/AgCl. The assembly of direct borohydride-hydrogen peroxide fuel cell (DBHPFC) exhibits a peak power density of 45.2 mW·cm-2, demonstrating durable stability over a continuous operation period of 120 h. This investigation providing evidence that the fabrication of heterostructured catalysts based on CeO2 for HPRR is a viable approach for the development of high-efficiency electrocatalysts in fuel cell technology.

9.
Bioprocess Biosyst Eng ; 47(8): 1307-1319, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38698218

RESUMO

Our study specifically explores the biosynthesis of copper-silver bimetallic nanoparticles (Cu-Ag BMNPs) using Argyreia nervosa (AN) plant leaf green extract as a versatile agent for capping, reducing, and stabilizing. This biosynthesis method is characterized by its simplicity and cost-effectiveness, utilizing silver nitrate (AgNO3) and cupric oxide (CuO) as precursor materials. Our comprehensive characterization of the Cu-Ag BMNPs, employing techniques such as X-ray diffraction (XRD), UV-Vis spectrometry, scanning electron microscopy (SEM), Zetasizer, and Fourier transformed infrared spectrometry (FTIR). FTIR analysis reveals biofunctional groups and chemical bands, while SEM and XRD analyses provide morphological and structural details. To evaluate the antimicrobial properties of the Cu-Ag BMNPs, we conducted disc diffusion and minimum inhibitory concentration (MIC) assays against Escherichia coli (E. coli), with results compared to the standard gentamicin antibiotic. It is observed that the 2% and 5% CuO concentrations of AN Cu-Ag BMNPs exhibit substantial antibacterial activity in comparison to AN extract when tested on EPEC. Among these, the Cu-Ag BMNPs at a 2% concentration demonstrate higher antibacterial activity, potentially attributed to the enhanced dispersion of BMNPs facilitated by the lower CuO doping concentration. These two assays showcased the improved antimicrobial activity of Cu-Ag BMNPs, highlighting their synergistic effect, characterized by high MIC values and a broad zone of inhibition in the disc diffusion tests against E. coli. These results emphasize the significant antibacterial potential of the synthesized BMNPs, with a medicinal plant AN leaf extract playing a pivotal role in enhancing antibacterial activity.


Assuntos
Antibacterianos , Cobre , Escherichia coli , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Folhas de Planta , Prata , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/biossíntese , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Cobre/química , Prata/química , Prata/farmacologia , Folhas de Planta/química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Nanomaterials (Basel) ; 14(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38786809

RESUMO

The application of electrochemical hydrogen evolution reaction (HER) for renewable energy conversion contributes to the ultimate goal of a zero-carbon emission society. Metal phosphides have been considered as promising HER catalysts in the alkaline environment, which, unfortunately, is still limited owing to the weak adsorption of H* and easy dissolution during operation. Herein, a bimetallic NiCoP-2/NF phosphide is constructed on nickel foam (NF), requiring rather low overpotentials of 150 mV and 169 mV to meet the current densities of 500 and 1000 mA cm-2, respectively, and able to operate stably for 100 h without detectable activity decay. The excellent HER performance is obtained thanks to the synergetic catalytic effect between Ni and Co, among which Ni is introduced to enhance the intrinsic activity and Co increases the electrochemically active area. Meanwhile, the protection of the externally generated amorphous phosphorus oxide layer improves the stability of NiCoP/NF. An electrolyser using NiCoP-2/NF as both cathode and anode catalysts in an alkaline solution can produce hydrogen with low electric consumption (overpotential of 270 mV at 500 mA cm-2).

11.
Cell Mol Biol Lett ; 29(1): 50, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594618

RESUMO

BACKGROUND: Melanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma. METHODS: We evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy. RESULTS: Our results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway. CONCLUSION: These findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.


Assuntos
Antineoplásicos , Imidazóis , Imunoconjugados , Melanoma , Oximas , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Neoplasias Cutâneas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Fosfatidilinositol 3-Quinases , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Imunoconjugados/genética , Imunoconjugados/uso terapêutico , Mutação
12.
Adv Mater ; 36(23): e2313835, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38427844

RESUMO

Multinary metal chalcogenides hold considerable promise for high-energy potassium storage due to their numerous redox reactions. However, challenges arise from issues such as volume expansion and sluggish kinetics. Here, a design featuring a layered ternary Bi0.4Sb1.6Te3 anchored on graphene layers as a composite anode, where Bi atoms act as a lattice softening agent on Sb, is presented. Benefiting from the lattice arrangement in Bi0.4Sb1.6Te3 and structure, Bi0.4Sb1.6Te3/graphene exhibits a mitigated expansion of 28% during the potassiation/depotassiation process and demonstrates facile K+ ion transfer kinetics, enabling long-term durability of 500 cycles at various high rates. Operando synchrotron diffraction patterns and spectroscopies including in situ Raman, ex situ adsorption, and X-ray photoelectron reveal multiple conversion and alloying/dealloying reactions for potassium storage at the atomic level. In addition, both theoretical calculations and electrochemical examinations elucidate the K+ migration pathways and indicate a reduction in energy barriers within Bi0.4Sb1.6Te3/graphene, thereby suggesting enhanced diffusion kinetics for K+. These findings provide insight in the design of durable high-energy multinary tellurides for potassium storage.

13.
Int J Health Sci (Qassim) ; 18(2): 33-37, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455601

RESUMO

Objectives: The objectives of the study are to investigate the synergistic effect of oxaliplatin (oxa) and punicalagin (pun) on the death of colon cancer cells (Caco-2) by apoptosis and autophagy. Methods: The effects of the combined treatments (5 µM oxa + 50 µM pun, 5 µM oxa + 75 µM pun, 20 µM oxa + 50 µM pun, and 5 µM oxa + 75 µM pun) were compared with untreated Caco2 cells (control) or cells treated with oxa alone. Apoptosis was detected using an Annex in V FITC flow cytometry assay and poly (ADP-ribose) polymerase cleavage by western blotting. Light chain 3 was detected by western blotting as an autophagy marker. Results: The combined treatments significantly increased the number of apoptotic cells in comparison to untreated cells or cells treated with oxa alone. By contrast, the combined treatments had no significant effect on autophagy. Conclusion: The combined treatment significantly promoted cell death through apoptosis while maintaining a basal level of autophagy.

14.
Adv Mater ; 36(37): e2311434, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38377407

RESUMO

Dual-atom catalysts (DACs) hold a higher metal atom loading and provide greater flexibility in terms of the structural characteristics of their active sites in comparison to single-atom catalysts. Consequently, DACs hold great promise for achieving improved catalytic performance. This article aims to provide a focused overview of the latest advancements in DACs, covering their synthesis and mechanisms in reversible oxygen electrocatalysis, which plays a key role in sustainable energy conversion and storage technologies. The discussion starts by highlighting the structures of DACs and the differences in diatomic coordination induced by various substrates. Subsequently, the state-of-the-art fabrication strategies of DACs for oxygen electrocatalysis are discussed from several different perspectives. It particularly highlights the challenges of increasing the diatomic loading capacity. More importantly, the main focus of this overview is to investigate the correlation between the configuration and activity in DACs in order to gain a deeper understanding of their active roles in oxygen electrocatalysis. This will be achieved through density functional theory calculations and sophisticated in situ characterization technologies. The aim is to provide guidelines for optimizing and upgrading DACs in oxygen electrocatalysis. Additionally, the overview discusses the current challenges and future prospects in this rapidly evolving area of research.

15.
Nanomicro Lett ; 16(1): 139, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421549

RESUMO

The exploration of sustainable energy utilization requires the implementation of advanced electrochemical devices for efficient energy conversion and storage, which are enabled by the usage of cost-effective, high-performance electrocatalysts. Currently, heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications. Compared to conventional catalysts, atomically dispersed metal atoms in carbon-based catalysts have more unsaturated coordination sites, quantum size effect, and strong metal-support interactions, resulting in exceptional catalytic activity. Of these, dual-atomic catalysts (DACs) have attracted extensive attention due to the additional synergistic effect between two adjacent metal atoms. DACs have the advantages of full active site exposure, high selectivity, theoretical 100% atom utilization, and the ability to break the scaling relationship of adsorption free energy on active sites. In this review, we summarize recent research advancement of DACs, which includes (1) the comprehensive understanding of the synergy between atomic pairs; (2) the synthesis of DACs; (3) characterization methods, especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy; and (4) electrochemical energy-related applications. The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules, such as oxygen reduction reaction, CO2 reduction reaction, hydrogen evolution reaction, and N2 reduction reaction. The future research challenges and opportunities are also raised in prospective section.

16.
J Exp Clin Cancer Res ; 43(1): 56, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38403634

RESUMO

BACKGROUND: Ovarian cancer (OC) is a prevalent malignancy in the female reproductive system, and developing effective targeted therapies for this disease remains challenging. The aim of this study was to use clinically-relevant OC models to evaluate the therapeutic effectiveness of RC48, an antibody-drug conjugate (ADC) targeting HER2, either alone or in combination with the VEGFR inhibitor Cediranib Maleate (CM), for the treatment of advanced OC. METHODS: OC tumor specimens and cell lines were analyzed to determine HER2 and VEGFR expression by Western blot, immunocytochemistry and immunofluorescence. Moreover, the OC cell lines, cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models were treated with RC48 and/or CM and then subjected to cell proliferation, viability, apoptosis, and tumor growth analyses to evaluate the feasibility of combination therapy for OC both in vitro and in vivo. Additionally, RNA-Seq was performed to investigate the critical mechanism underlying the combination therapy of RC48 and CM. RESULTS: Our results demonstrated that RC48 alone effectively targeted and inhibited the growth of HER2-positive OC tumors in both cell lines and PDX models. Furthermore, the combination of RC48 and CM synergistically induced tumor regression in human OC cell lines, as well as CDX and PDX models. Mechanistically, we observed that the combination treatment inhibited the growth of OC cells involved inducing apoptosis and suppressing cell motility. RNA-seq analysis provided further mechanistic insights and revealed that co-administration of RC48 and CM downregulated multiple cancer-related pathways, including the AKT/mTOR pathway, cell cycle, and cell proliferation. Notably, our data further confirmed that the PI3K-AKT pathway played a key role in the inhibition of proliferation triggered by combinational treatment of RC48 and CM in OC cells. CONCLUSIONS: These findings provide a preclinical framework supporting the potential of dual targeting HER2 and VEGFR as a promising therapeutic strategy to improve outcomes in patients with OC.


Assuntos
Neoplasias Ovarianas , Proteínas Proto-Oncogênicas c-akt , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Carcinoma Epitelial do Ovário , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Proliferação de Células , Linhagem Celular Tumoral
17.
Eur J Pharmacol ; 967: 176379, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38342361

RESUMO

Dopa and tetrahydrobiopterin (BH4) supplementation are recommended therapies for the dopa-responsive dystonia caused by GTP cyclohydrolase 1 (GCH1, also known as GTPCH) deficits. However, the efficacy and mechanisms of these therapies have not been intensively studied yet. In this study, we tested the efficacy of dopa and BH4 therapies by using a novel GTPCH deficiency mouse model, Gch1KI/KI, which manifested infancy-onset motor deficits and growth retardation similar to the patients. First, dopa supplementation supported Gch1KI/KI mouse survival to adulthood, but residual motor deficits and dwarfism remained. Interestingly, RNAseq analysis indicated that while the genes participating in BH4 biosynthesis and regeneration were significantly increased in the liver, no significant changes were observed in the brain. Second, BH4 supplementation alone restored the growth of Gch1KI/KI pups only in early postnatal developmental stage. High doses of BH4 supplementation indeed restored the total brain BH4 levels, but brain dopamine deficiency remained. While total brain TH levels were relatively increased in the BH4 treated Gch1KI/KI mice, the TH in the striatum were still almost undetectable, suggesting differential BH4 requirements among brain regions. Last, the growth of Gch1KI/KI mice under combined therapy outperformed dopa or BH4 therapy alone. Notably, dopamine was abnormally high in more than half, but not all, of the treated Gch1KI/KI mice, suggesting the existence of variable synergetic effects of dopa and BH4 supplementation. Our results provide not only experimental evidence but also novel mechanistic insights into the efficacy and limitations of dopa and BH4 therapies for GTPCH deficiency.


Assuntos
Biopterinas/análogos & derivados , Di-Hidroxifenilalanina , Dopamina , Fenilcetonúrias , Humanos , Camundongos , Animais , GTP Cicloidrolase/genética , Modelos Animais de Doenças
18.
Environ Res ; 250: 118363, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38331141

RESUMO

The widespread existence of antibiotics in the environment has attracted growing concerns regarding the potential adverse effects on aquatic organisms, ecosystems, and human health even at low concentrations. Extensive efforts have been devoted to developing new methods for effective elimination of antibiotics from wastewater. Herein, a novel process of Fe2+ catalytically enhanced vacuum ultraviolet (VUV) irradiation was proposed as a promising approach for the removal of antibiotic trimethoprim (TMP) in water. Compared with UVC photolysis, VUV photolysis, and UVC/Fe2+, VUV/Fe2+ could increase the pseudo-first-order reaction rate constant of TMP removal by 6.6-38.4 times and the mineralization rate by 36.5%-59.9%. The excellent performance might originate from the synergistic effect of VUV and Fe2+, i.e., VUV irradiation could effectively split water and largely accelerate the Fe3+/Fe2+ cycle to generate more reactive oxygen species (ROS). EPR results indicated that •OH and O2•- were identified as the main ROS in the UVC/Fe2+ and VUV/Fe2+ processes, while •OH, O2•-, and 1O2 were involved in the VUV process. The operating parameters, such as Fe2+ dosage and initial TMP contents, were evaluated and optimized. Up to 8 aromatic intermediates derived from hydroxylation, demethylation, carbonylation, and methylene group cleavage were identified by UPLC-QTOF-MS/MS technique, the possible pathways of TMP degradation were proposed. Finally, the acute and chronic toxicity of intermediates formed during TMP degradation in the VUV/Fe2+ process were also evaluated.


Assuntos
Fotólise , Trimetoprima , Raios Ultravioleta , Poluentes Químicos da Água , Trimetoprima/química , Trimetoprima/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Cinética , Antibacterianos/química , Antibacterianos/toxicidade , Ferro/química , Vácuo , Catálise , Animais
19.
Adv Mater ; 36(21): e2313596, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408470

RESUMO

Understanding the synergism between the metal site and acid site is of great significance in boosting the efficiency of bi-functional catalysts in many heterogeneous reactions, particularly in biomass upgrading. Herein, a "confined auto-redox" strategy is reported to fix CeO2-anchored Pt atoms on the inner wall of a ZSM-5 cage, achieving the target of finely controlling the placements of the two active sites. Compared with the conventional surface-supported counterpart, the encapsulated Pt/CeO2@ZSM-5 catalyst possesses remarkably-improved activity and selectivity, which can convert >99% furfural into cyclopentanone with 97.2% selectivity in 6 h at 160 °C. Besides the excellent catalytic performance, the ordered metal-acid distribution also makes such kind of catalyst an ideal research subject for metal-acid interactions. The following mechanization investigation reveals that the enhancement is strongly related to the unique encapsulation structure, which promotes the migration of the reactants over different active sites, thereby contributing to the tandem reaction.

20.
Talanta ; 271: 125677, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38245956

RESUMO

A MoS2-based nanotherapeutic platform was developed for synergetic photothermal and photodynamic anti-tumor therapy. AIEgens TFPy-SH molecules were intercalated into MoS2 nanosheets (MoS2 NSs) with S-deficiencies to give the nanocomposite MoS2-TFPy. The AIEgens intercalation expanded the interlayer spacing of MoS2 NSs and induced the transform of MoS2 crystal phase from 2H to 1T, offering MoS2-TFPy nanocomposite high molar absorption coefficient (5.65 L g-1 cm-1), excellent photothermal conversion efficiency under near-infrared (NIR) laser irradiation (38.3%), and favorable intracellular reactive oxygen species (ROS) generation capacity. The positively charged MoS2-TFPy were mainly distributed in mitochondria after cell up-taking, and achieved 1+1>2 anti-tumor effect attributed to its favorable photothermal and photodynamic properties. The high structure and physiological stability, favorable biocompatibility, excellent photothermal and photodynamic therapy effect make the MoS2-TFPy nanoplatform an promising candidate in biomedical clinical applications.


Assuntos
Nanocompostos , Fotoquimioterapia , Molibdênio , Mitocôndrias , Espécies Reativas de Oxigênio
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