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1.
J Colloid Interface Sci ; 674: 79-91, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38917714

RESUMO

Exploring strategies to improve the near-infrared response of photocatalysts is an urgent challenge that can be overcome by utilizing upconversion (UC) luminescence to enhance photocatalysis. This paper reports the fabrication of a ZnO/Bi3Ti2O8F:Yb3+, Er3+ (ZnO/BTOFYE) Z-scheme heterojunction based on a Bi3Ti2O8F:Yb3+, Er3+ (BTOFYE) UC photocatalyst via electrostatic self-assembly. Fermi energy difference at the interface of BTOFYE and ZnO generates a strong internal electric field (IEF) in the Z-scheme heterojunction, offering a novel charge transfer mode that promotes carrier transfer and separation while retaining the strong redox capability. These results are confirmed through in situ X-ray photoelectron spectroscopy, in situ Kelvin probe force microscopy, electron spin resonance, and density functional theory calculations. In addition, the effect of the IEF on the UC luminescence process of Er3+ enhances the luminescence intensity, considerably improving the UC utilization efficiency. The optimal ZnO/BTOFYE degrades 64 % of ciprofloxacin in 120 min, which is 2.3 times more than that degraded by BTOFYE. Overall, the results of this study offer a reference for the rational development of high efficiency UC photocatalysts by generating IEF in Z-scheme heterojunctions.

2.
Colloids Surf B Biointerfaces ; 238: 113923, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692173

RESUMO

The rapid advancement of photodynamic therapy (PDT) antibacterial materials has led to promising alternatives to antibiotics for treating bacterial infections. However, antibacterial drugs have poor light absorption and utilization rates, which limits their practical application. Constructing two-dimensional (2D) heterojunctions from materials with matching photophysical properties has emerged as a highly effective strategy for achieving high-efficiency photo-antibacterial performance. Here, we designed and prepared an atom co-sharing Bi/Bi4O5Br2 nanosheet heterojunction by a simple in situ reduction. This heterojunction material combines outstanding biocompatibility with excellent bactericidal efficiency, which exceeded 90 % against Escherichia coli (a Gram-negative bacterium) and Staphylococcus aureus (a Gram-positive bacterium) under visible light irradiation, around nine-fold higher than that with pure Bi4O5Br2 nanosheets. The results suggest that localized surface plasmon resonance (LSPR) of shared Bi atoms on the Bi4O5Br2 nanosheets promotes light utilization and the separation and transfer of photo-generated charges, thus producing more abundant reactive oxygen species (ROS), which can partake in the PDT antibacterial effect. Our study underscores the potential utility of LSPR-enhanced Bi-based nanosheet heterojunctions for safe and efficient PDT to combat bacterial infections.


Assuntos
Antibacterianos , Bismuto , Escherichia coli , Luz , Nanoestruturas , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Nanoestruturas/química , Bismuto/química , Bismuto/farmacologia , Catálise , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Espécies Reativas de Oxigênio/metabolismo , Ressonância de Plasmônio de Superfície , Fotoquimioterapia , Tamanho da Partícula
3.
Adv Healthc Mater ; : e2303836, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507269

RESUMO

Chronic diabetic wounds pose significant challenges due to uncontrolled bacterial infections, prolonged inflammation, and impaired angiogenesis. The rapid advancement of photo-responsive antibacterial therapy showed promise in addressing these complex issues, particularly utilizing 2D heterojunction materials, which offer unique properties. Herein, we designed an in situ sprayed Bi/BiOCl 0D/2D heterojunction composite fibrin gel with the characteristics of rapid formation and effective near-infrared activation for the treatment of non-healing diabetes-infected wounds. The sprayed composite gel can provide protective shielding for skin tissues and promote endothelial cell proliferation, vascularization, and angiogenesis. The Bi/BiOCl 0D/2D heterojunction, with its localized surface plasmon resonance (LSPR), can overcome the wide bandgap limitation of BiOCl, enhancing the generation of local heat and reactive oxygen species under near-infrared irradiation. This facilitated bacterial elimination and reduced inflammation, supporting the accelerated healing of diabetes-infected wounds. Our study underscores the potential of LSPR-enhanced heterojunctions as advanced wound therapies for chronic diabetic wounds. This article is protected by copyright. All rights reserved.

4.
Polymers (Basel) ; 15(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38006151

RESUMO

Synthetic adhesives play a crucial role in holding together solid materials through interfacial interactions. Thermoplastic and thermosetting adhesives are important types of synthetic adhesives, with thermoplastic adhesives being reassemblable and thermosetting adhesives exhibiting high adhesive strength and creep resistance. However, there is a need to combine the advantages of both types and develop high bonding strength, reassemblable adhesives. Here, epoxidized soybean oil (ESO) was used to prepare adhesive networks and Diels-Alder bonds were incorporated to enhance reassembly ability. The ESO was functionalized with furyl groups and cross-linked via the reaction between furyl and imide groups to involve the Diels-Alder bonds. The resulting adhesive exhibited good solvent resistance and mechanical properties, which could be regulated by adjusting the quantity of cross-linker. The prepared adhesives also demonstrated self-healing capabilities, as the scratch on the surface gradually diminished with heating. Additionally, the adhesives showed the ability to undergo recycling without significant changes in properties. The prepared adhesives exhibited hydrophilicity and the flow characteristics during reassembly were characterized by a decrease in torque. This study provides a promising approach for the development of synthetic adhesives with reassembly ability, which has important implications for the field of bonding.

5.
J Int Med Res ; 51(10): 3000605231204429, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37848343

RESUMO

OBJECTIVE: We aimed to investigate the diagnostic value of different laboratory indicators in combination with total prostate-specific antigen (TPSA) for prostate cancer (PCa). METHODS: In this retrospective study, we selected 291 patients who underwent prostate biopsy. Patients were divided into the benign prostatic hyperplasia group and the PCa group. In both groups, patients were again divided into a group with TPSA 4.0-10.0 ng/mL and a group with TPSA >10.0 ng/mL. Clinical data including age, pre-puncture TPSA, free prostate-specific antigen (FPSA), and prostate volume (PV) were collected from all patients. We calculated the metrics PSA/PV (prostate-specific antigen density, PSAD), age/PV (AVR), age × PV/TPSA (PSA-AV), and (FPSA/TPSA)/PSAD [(F/T)/PSAD]). We plotted receiver operating characteristic (ROC) curves and calculated the area under the ROC curve (AUC). RESULTS: We found statistically significant differences in PV, PSAD, AVR, PSA-AV, and (F/T) PSAD for patients with TPSA 4.0-10.0 ng/mL and TPSA >10 ng/mL. We further plotted the ROC of individual or combined indices in different subgroups and calculated the AUC. We found that the diagnostic efficacy of the combined indices was higher with TPSA >10 ng/mL. CONCLUSION: The combination of TPSA with multiple indicators may improve diagnostic accuracy for PCa.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico , Estudos Retrospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Próstata/patologia , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patologia , Curva ROC
6.
Polymers (Basel) ; 15(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37631545

RESUMO

Thermosetting adhesives are commonly utilized in various applications. However, covalent cross-linked networks prevent thermosetting adhesives from being re-assembled, which necessitates higher machining precision. Additionally, the primary raw materials used in adhesive preparation are derived from non-renewable petroleum resources, which further constrain adhesive development. In this study, a recyclable adhesive was developed by incorporating dynamic boronic esters into epoxy resin derived from soybean oil. The successful synthesis of epoxidized soybean oil and boronic esters was confirmed through the analysis of proton nuclear magnetic resonance spectra and differential scanning calorimetry results. Swelling tests and tensile curves demonstrated the presence of covalently cross-linked networks. Self-healing and reprocessing experiments indicated that the cross-linked network topology could be re-assembled under mild conditions.

7.
Adv Sci (Weinh) ; 10(13): e2207514, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808714

RESUMO

Developing full-spectrum photocatalysts with simultaneous broadband light absorption, excellent charge separation, and high redox capabilities is becoming increasingly significant. Herein, inspired by the similarities in crystalline structures and compositions, a unique 2D-2D Bi4 O5 I2 /BiOBr:Yb3+ ,Er3+ (BI-BYE) Z-scheme heterojunction with upconversion (UC) functionality is successfully designed and fabricated. The co-doped Yb3+ and Er3+ harvest near-infrared (NIR) light and then convert it into visible light via the UC function, expanding the optical response range of the photocatalytic system. The intimate 2D-2D interface contact provides more charge migration channels and enhances the Förster resonant energy transfer of BI-BYE, leading to significantly improved NIR light utilization efficiency. Density functional theory (DFT) calculations and experimental results confirm that the Z-scheme heterojunction is formed and that this heterojunction endows the BI-BYE heterostructure with high charge separation and strong redox capability. Benefit from these synergies, the optimized 75BI-25BYE heterostructure exhibits the highest photocatalytic performance for Bisphenol A (BPA) degradation under full-spectrum and NIR light irradiation, outperforming BYE by 6.0 and 5.3 times, respectively. This work paves an effective approach for designing highly efficient full-spectrum responsive Z-scheme heterojunction photocatalysts with UC function.

8.
Nanoscale ; 15(4): 1849-1859, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36602168

RESUMO

The coupling between piezoelectricity and photoexcitation is an attractive method for improving the photocatalytic efficiency of semiconductors. Herein, a novel layered perovskite photocatalyst Bi2NdO4Cl (BNOC) has been successfully prepared via solid-state reaction. PFM results confirm that BNOC has piezoelectricity, and its piezo-photocatalytic degradation performance was evaluated for the first time using tetracycline hydrochloride (TH) as a pollutant model. The results show that the piezo-photocatalytic degradation rate constant is about 1.5 times higher than the sum of the individual photo- and piezo-catalytic components. This synergistic enhancement can be attributed to the band tilting-induced piezoelectric polarization charges and formation of a piezoelectric field, which accelerates the photoinduced charge carrier separation and effectively enhanced the photocatalytic performance. This work may facilitate the development of novel piezoelectric photocatalytic materials that are highly sensitive to the mechanical energy of discrete fluids, and offer ideas for piezo-photocatalysis in environmental applications.

9.
Org Lett ; 24(41): 7701-7706, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36227065

RESUMO

Herein, we present a strategy for the preparation of 3'-fluorinated nucleoside analogues via the aminocatalytic, electrophilic fluorination of readily accessible and bench-stable 2'-ketonucleosides. Initially developed to facilitate the manufacture of 3'-fluoroguanosine (3'-FG)─a substructure of anticancer therapeutic MK-1454─this strategy has been extended to the synthesis of a variety of 3'-fluoronucleosides. Finally, we demonstrate the utility of the 2'-ketonucleoside synthon as a platform for further diversification and suggest that this methodology should be broadly applicable to the discovery of novel nucleoside analogues.

10.
ACS Appl Mater Interfaces ; 14(32): 36966-36979, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35921222

RESUMO

Bacterial infection greatly affects the rate of wound healing. Both photothermal and photodynamic antibacterial therapies activated by near-infrared (NIR) light with semiconductor nanomedicine are two effective approaches to address bacterial infections, but they cannot coexist synergistically to kill bacteria more efficiently because of the limitation of the band structure. Here, inspired by the natural core-shell structure and photosynthesis simultaneously, polypyrrole (PPy) is synthesized in the two-dimensional restricted area of the layered bismuth oxychloride (BiOCl) nanosheets through the in situ ultrasonic recombination method. The atomic-level interface contact and bonding formed in the PPy-BiOCl intercalated nanosheets not only improve the light-to-heat conversion capabilities of PPy but also promote the transmission of PPy photogenerated charge carriers to the BiOCl semiconductor. The nanocomposites take advantage of the deeper tissue penetration under NIR light irradiation and exhibit excellent photothermal and photodynamic synergistic antibacterial activity. In addition, PPy-BiOCl intercalated nanosheets have good biocompatibility and accelerate wound healing through their antimicrobial activity and skin repair function. The space-confined synthesis of thin PPy nanosheets in layered structures offers an efficient NIR photoresponsive nanomedicine for the treatment of pathogen infection, with promising applications in infected wound healing.


Assuntos
Polímeros , Pirróis , Antibacterianos/química , Antibacterianos/farmacologia , Bismuto , Polímeros/química , Pirróis/química , Pirróis/farmacologia , Cicatrização
11.
Nanoscale ; 14(35): 12909-12917, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36043419

RESUMO

Rare earth (RE) ions combined with two-dimensional (2D) semiconductors can exhibit unexpected optical properties. However, fluorescence quenching has always been inevitable due to defects associated with the synthesis and doping of 2D materials. In this work, we reported an efficient upconversion (UC) enhancement of Er3+ doped BiOCl nanosheets, utilizing a defect engineering strategy conversely rather than eliminating defects. Experiments and theoretical calculations provide evidence that oxygen vacancies (OVs) and lattice strain are simultaneously formed in the BiOCl:Er3+ nanosheets through self-doping of Cl- ions. Under 980 nm excitation, samples doped with 300 mol% Cl- ions exhibit the best luminescent emission, and the green and red UC emissions are enhanced 3.5 and 15 times, respectively. We showed that the OVs in the 2D semiconductor can act as energy bridges to transfer charges to the Er3+ energy level, enriching the electron population at the excited levels; while, the lattice strain enhances the energy transfer and charge accumulation, which synergistically enhance the UC luminescence. This research provides a new insight into the development of defect engineering for UC PL in 2D nanomaterials.

13.
Mater Today Bio ; 15: 100292, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35634172

RESUMO

Recurrent bacterial infection is a major problem that threatens the tissue repair process. However, most current therapeutic strategies fail to deal with management of the overlap dynamics of bacterial killing and tissue repair. Here, in accord with the different responses of eukaryotic and prokaryotic cells to electric potential, we developed high performance photoelectric BiOCl nanosheets that dynamically switch between conditions that favor either tissue regrowth or antibacterial microenvironments due to light stimulated and bi-modal switching of their surface electrical polarization. In vitro assays demonstrate that, under light illumination, the mannitol modified BiOCl nanosheets show high relative surface potential and achieve robust antibacterial performance. Conversely, under dark conditions, the nanosheets exhibit relatively low surface potential and promote Bone Marrow Stem Cell (BMSCs) proliferation. In vivo studies indicate that BiOCl nanosheets with light switch capabilities promote the significant regeneration of infected skin wounds. This work offers a new insight into treating recurrent bacterial infections with photoelectric biomaterials for light controlled selection of alternative electrical microenvironments, thereby benefiting the capability for either antisepsis or repair of damaged tissues.

14.
J Med Chem ; 65(8): 6001-6016, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35239336

RESUMO

3,3-Disubstituted oxetanes have been utilized as bioisosteres for gem-dimethyl and cyclobutane functionalities. We report the discovery of a novel class of oxetane indole-amine 2,3-dioxygenase (IDO1) inhibitors suitable for Q3W (once every 3 weeks) oral and parenteral dosing. A diamide class of IDO inhibitors was discovered through an automated ligand identification system (ALIS). Installation of an oxetane and fluorophenyl dramatically improved the potency. Identification of a biaryl moiety as an unconventional amide isostere addressed the metabolic liability of amide hydrolysis. Metabolism identification (Met-ID)-guided target design and the introduction of polarity resulted in the discovery of potent IDO inhibitors with excellent pharmacokinetic (PK) profiles in multiple species. To enable rapid synthesis of the key oxetane intermediate, a novel oxetane ring cyclization was also developed, as well as optimization of a literature route on kg scale. These IDO inhibitors may enable unambiguous proof-of-concept testing for the IDO1 inhibition mechanism for oncology.


Assuntos
Inibidores Enzimáticos , Éteres Cíclicos , Amidas , Ciclização , Inibidores Enzimáticos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo
15.
J Am Chem Soc ; 144(13): 5855-5863, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35333525

RESUMO

As practitioners of organic chemistry strive to deliver efficient syntheses of the most complex natural products and drug candidates, further innovations in synthetic strategies are required to facilitate their efficient construction. These aspirational breakthroughs often go hand-in-hand with considerable reductions in cost and environmental impact. Enzyme-catalyzed reactions have become an impressive and necessary tool that offers benefits such as increased selectivity and waste limitation. These benefits are amplified when enzymatic processes are conducted in a cascade in combination with novel bond-forming strategies. In this article, we report a highly diastereoselective synthesis of MK-1454, a potent agonist of the stimulator of interferon gene (STING) signaling pathway. The synthesis begins with the asymmetric construction of two fluoride-bearing deoxynucleotides. The routes were designed for maximum convergency and selectivity, relying on the same benign electrophilic fluorinating reagent. From these complex subunits, four enzymes are used to construct the two bridging thiophosphates in a highly selective, high yielding cascade process. Critical to the success of this reaction was a thorough understanding of the role transition metals play in bond formation.


Assuntos
Produtos Biológicos , Produtos Biológicos/química , Catálise
16.
Int J Oncol ; 60(5)2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35348188

RESUMO

Following the publication of the above paper, a concerned reader drew to the Editor's attention that one of the fluorescence microscopic images featured in Fig. 4A had previously appeared in a different form (a portion of data in a different orientation) in another article published by the same authors [Yu J, Zhao L, Li Y, Li N, He M, Bai H, Yu Z, Zheng Z, Mi X, Wang E and We M: Silencing of Fanconi anemia complementation group F exhibits potent chemosensitization of mitomycin C activity in breast cancer cells. J Breast Cancer 16: 291­299, 2013]. Furthermore, the data panel shown for the 'MDA­MB­231/untreated' experiment in Fig. 4A in the above paper appeared to be duplicated as the 'MDA­MB­231/MMC + control shRNA' experiment, albeit stained differently. After having received a request from the authors to publish a corrigendum in view of the errors identified in Fig. 4 of the above paper, the Editor of International Journal of Oncology has conducted an independent investigation of the matter and determined that this article should be retracted from the Journal on account of a lack of confidence in the presented data. Upon receiving this decision, the authors were not in agreement that the paper should be retracted. The Editor regrets any inconvenience that has been caused to the readership of the Journal. [the original article was published in International Journal of Oncology 45: 129­138, 2014; DOI: 10.3892/ijo.2014.2400].

17.
J Environ Sci (China) ; 115: 76-87, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34969479

RESUMO

For better use of solar energy, the development of efficient broadband photocatalyst has attracted extraordinary attention. In this study, a ternary composite consisting of Sr2LaF7:Yb3+,Er3+ upconversion (UC) nanocrystals and Bi nanoparticles loaded BiOBr nanosheets with oxygen vacancies (OVs, SLFBB) was designed and synthesized by multistep solvent-thermal method. Mechanisms of in-situ formation of Bi nanoparticles and OVs in BiOBr/Sr2LaF7:Yb3+,Er3+ composites (SFLB) are clarified. The Bi metal and OVs enhanced the light-harvesting capacity in the region of visible-near-infrared (Vis-NIR), and promoted the separation of electron-hole (e-/h+) pairs. Furthermore, the surface plasmon resonance (SPR) effect of Bi metal can improve the energy transfer from Sr2LaF7:Yb3+,Er3+ to BiOBr via nonradiative energy transfer process, resulting in enhancing the light utilization from upconverting NIR into Vis light. Due to the synergistic effects of UC function, SPR and OVs, the SFLBB exhibited obviously enhanced photocatalytic ability for the degradation of BPA with a rate of 8.9 × 10-3 min-1, which is about 2.78 times higher than 3.2 × 10-3 min-1 of BiOBr (BOB) under UV-Vis-NIR light irradiation. This work provides a novel strategy for the project of high-efficiency Bismuth-based broadband photocatalysts, which is helpful to further understand the mechanism of enhanced photocatalysis by UC function and plasmonic effect.


Assuntos
Bismuto , Oxigênio , Catálise , Luz
18.
Sensors (Basel) ; 21(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34640646

RESUMO

Hypochlorous acid (HOCl) generates from the reaction between hydrogen peroxide and chloride ions via myeloperoxidase (MPO)-mediated in vivo. As very important reactive oxygen species (ROS), hypochlorous acid (HOCl)/hypochlorite (OCl-) play a crucial role in a variety of physiological and pathological processes. However, excessive or misplaced production of HOCl/OCl- can cause variety of tissue damage and human diseases. Therefore, rapid, sensitive, and selective detection of OCl- is very important. In recent years, the fluorescent probe method for detecting hypochlorous acid has been developed rapidly due to its simple operation, low toxicity, high sensitivity, and high selectivity. In this review, the progress of recently discovered fluorescent probes for the detection of hypochlorous acid was summarized with the aim to provide useful information for further design of better fluorescent probes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Humanos , Peróxido de Hidrogênio , Peroxidase
19.
Chem Sci ; 12(26): 9031-9036, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34276931

RESUMO

An efficient route to the HCV antiviral agent uprifosbuvir was developed in 5 steps from readily available uridine in 50% overall yield. This concise synthesis was achieved by development of several synthetic methods: (1) complexation-driven selective acyl migration/oxidation; (2) BSA-mediated cyclization to anhydrouridine; (3) hydrochlorination using FeCl3/TMDSO; (4) dynamic stereoselective phosphoramidation using a chiral nucleophilic catalyst. The new route improves the yield of uprifosbuvir 50-fold over the previous manufacturing process and expands the tool set available for synthesis of antiviral nucleotides.

20.
Light Sci Appl ; 10(1): 140, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234097

RESUMO

Transparent glass has been identified as a vital medium for three-dimensional (3D) optical information storage and multi-level encryption. However, it has remained a challenge for directly writing 3D patterning inside a transparent glass using semiconductor blue laser instead of high-cost femtosecond laser. Here, we demonstrate that rare earth ions doped transparent glass can be used as 3D optical information storage and data encryption medium based on their reversible transmittance and photoluminescence manipulation. The color of tungsten phosphate glass doped with rare earth ions change reversibly from light yellow to blue upon alternating 473 nm laser illumination and temperature stimulation, resulting in the reversible luminescence modulation. The information data could be repeatedly written and erased in arbitrary 3D space of transparent glass, not only showing the ability of the excellent reproducibility and storage capacity, but also opening opportunities in information security. The present work expands the application fields of luminescent glass, and it is conducive to develop a novel 3D data storage and information encryption media.

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