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1.
J Clin Transl Hepatol ; 11(2): 314-322, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-36643049

RESUMO

Background and Aims: Functional cure (FC) is characterized by the clearance of the hepatitis B surface antigen from the serum of patients with chronic hepatitis B (CHB). However, the level of intrahepatic covalently closed circular DNA (cccDNA) and hepatitis B virus (HBV) integration remains unclear. We conducted this study to determine them and reveal their value in the treatment of CHB. Methods: There were two sessions to elucidate the changes in intrahepatic cccDNA and HBV integration after antiviral therapy. In the first session, 116 patients were enrolled and divided into FC, non-functional cure (NFC), and CHB groups, including 48 patients with functionally cured CHB, 27 with CHB without functional cure after antiviral treatment, and 41 with treatment-naïve CHB. Patients were tested for both intrahepatic cccDNA and other viral markers. All patients in the FC group were followed up for at least 24 weeks to observe relapse. In the second session, another ten patients were included for in-depth whole-genome sequencing to analyze HBV integration. Results: Thirteen patients in the FC group were negative for intrahepatic cccDNA. Intrahepatic cccDNA was much higher in the CHB group compared with the FC group. Seven patients had HBsAg seroreversion, including two with virological relapse. Integration of HBV was detected in one (33.3%) functionally cured patients and in seven (100%) with CHB. 28.0% of the HBV breakpoints were assigned in the 1,500 nt to 1,900 nt range of the HBV genome. Conclusions: After achieving an FC, the rate of intrahepatic cccDNA and HBV integration was significantly reduced in patients with CHB. For those patients who cleared intrahepatic cccDNA, the chances of developing virological relapse were even lower.

2.
Nano Lett ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36706049

RESUMO

In kagome lattice, with the emergence of Dirac cones and flat band in electronic structure, it provides a versatile ground for exploring intriguing interplay among frustrated geometry, topology and correlation. However, such engaging interest is strongly limited by available kagome materials in nature. Here we report on a synthetic strategy of constructing kagome systems via self-intercalation of Fe atoms into the van der Waals gap of FeSe2 via molecular beam epitaxy. Using low-temperature scanning tunneling microscopy, we unveil a kagome-like morphology upon intercalating a 2 × 2 ordered Fe atoms, resulting in a stoichiometry of Fe5Se8. Both the bias-dependent STM imaging and theoretical modeling calculations suggest that the kagome pattern mainly originates from slight but important reconstruction of topmost Se atoms, incurred by the nonequivalent subsurface Fe sites due to the intercalation. Our study demonstrates an alternative approach of constructing artificial kagome structures, which envisions to be tuned for exploring correlated quantum states.

3.
Nat Commun ; 14(1): 354, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681684

RESUMO

Heteroatom-doping is a practical means to boost RuO2 for acidic oxygen evolution reaction (OER). However, a major drawback is conventional dopants have static electron redistribution. Here, we report that Re dopants in Re0.06Ru0.94O2 undergo a dynamic electron accepting-donating that adaptively boosts activity and stability, which is different from conventional dopants with static dopant electron redistribution. We show Re dopants during OER, (1) accept electrons at the on-site potential to activate Ru site, and (2) donate electrons back at large overpotential and prevent Ru dissolution. We confirm via in situ characterizations and first-principle computation that the dynamic electron-interaction between Re and Ru facilitates the adsorbate evolution mechanism and lowers adsorption energies for oxygen intermediates to boost activity and stability of Re0.06Ru0.94O2. We demonstrate a high mass activity of 500 A gcata.-1 (7811 A gRe-Ru-1) and a high stability number of S-number = 4.0 × 106 noxygen nRu-1 to outperform most electrocatalysts. We conclude that dynamic dopants can be used to boost activity and stability of active sites and therefore guide the design of adaptive electrocatalysts for clean energy conversions.


Assuntos
Rênio , Rutênio , Adsorção , Óxidos , Oxigênio
4.
Adv Sci (Weinh) ; : e2206442, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36698260

RESUMO

Despite the low cost and high capacity of Ni-rich layered oxides (NRLOs), their widespread implementation in electric vehicles is hindered by capacity decay and O release. These issues originate from chemo-mechanical heterogeneity, which is mainly related to oxygen anion redox (OAR). However, what to tune regarding OAR in NRLOs and how to tune it remains unknown. In this study, a close correlation between the OAR chemistry and Li/Ni antisite defects is revealed. Experiments and calculations show the opposite effects of aggregative and dispersive Li/Ni antisite defects on the NiO6 configuration and Ni spin state in NRLOs. The resulting broad or narrow spans for the energy bands caused by spin states lead to different OAR chemistries. By tuning the Li/Ni antisite defects to be dispersive rather than aggregative, the threshold voltage for triggering OAR is obviously elevated, and the generation of bulk-O2 -like species and O2 release at phase transition nodes is fundamentally restrained. The OAR is regulated from irreversible to reversible, fundamentally addressing structural degradation and heterogeneity. This study reveals the interaction of the Li/Ni antisite defect/OAR chemistry/chemo-mechanical heterogeneity and presents some insights into the design of high-performance NRLO cathodes.

5.
Adv Healthc Mater ; : e2202911, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36603589

RESUMO

Organic intercalation of layered nanomaterials is an attractive strategy to fabricate organic/inorganic superlattices for a wide range of promising applications. However, the synthesis of 2D organic/inorganic superlattice nanosheets remains a big challenge. Herein, the preparation of 2D polyaniline/MoO3- x (PANI/MoO3- x ) superlattice nanosheets via intercalation-induced morphological transformation from MoO3  nanobelts, as efficient Fenton-like reagents for chemodynamic therapy (CDT), is reported. Micrometer-long MoO3  nanobelts are co-intercalated with Na+ /H2 O followed by the guest exchange with aniline monomer for in situ polymerization to obtain PANI/MoO3- x nanosheets. Intriguingly, the PANI intercalation can induce the morphological transformation from long MoO3  nanobelts to 2D PANI/MoO3- x nanosheets along with the partial reduction of Mo6+ to Mo5+ , and generation of rich oxygen vacancies. More importantly, thanks to the PANI intercalation-induced activation, the PANI/MoO3- x nanosheets exhibit excellent Fenton-like catalytic activity for generation of hydroxyl radical (·OH) by decomposing H2 O2  compared with the MoO3  nanobelts. It is speculated that the good conductivity of PANI can facilitate electron transport during the Fenton-like reaction, thereby enhancing the efficiency of CDT. Thus, the polyvinylpyrrolidone-modified PANI/MoO3- x nanosheets can function as Fenton-like reagents for highly efficient CDT to kill cancer cells and eradicate tumors.

6.
Int J Biol Macromol ; 227: 134-145, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535347

RESUMO

Scutellaria baicalensis is a medicinal plant possessing abundant bioactive polysaccharides. This study aimed to optimize the ultrasound-assisted enzymatic extraction of S. baicalensis root polysaccharide (SRP) and investigate its hypoglycemic and immunomodulatory activities. The optimal extraction conditions found in this study were as follows: cellulase concentration 165.6 U/mL, temperature 57.3 °C, liquid-solid ratio 44.8 mL/g, time 50 min, and ultrasonic power 225 W; with the yield reached up to 12.27 %. The ion exchange and gel filtration chromatographies were used to obtain a purified SRP. The carbohydrate content of SRP was 85.09 %, with a relatively high content of uronic acids (11.27 %). The SRP had a molecular weight of 89.7 kDa and was composed of eight monosaccharides. The inhibitory activity of SRP against α-amylase and α-glucosidase was determined. It was revealed that SRP could effectively inhibit these two enzymes with IC50 values of 1.23 and 0.63 mg/mL, respectively. Finally, the immunomodulatory effect of SRP on the dendritic cell activation was investigated, and the expressions of MHC II, CD80, CD86, and CD40 increased by 1.56, 1.96, 1.75, and 1.70 times, respectively, by the SRP treatment. This work will provide a foundation for SRP's efficient extraction and utilization for diabetes and immune therapy.


Assuntos
Hipoglicemiantes , Plantas Medicinais , Hipoglicemiantes/farmacologia , Scutellaria baicalensis , Peso Molecular , Polissacarídeos/farmacologia , Antioxidantes/farmacologia
7.
J Urol ; 207(2): 417-423, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34544265

RESUMO

PURPOSE: Benign prostatic hyperplasia (BPH) is a common disease often manifested by lower urinary tract symptoms (LUTS). We previously found statins were associated with modest attenuations in prostate growth over time in REDUCE. We tested whether statins were associated with LUTS incidence in asymptomatic men and LUTS progression in symptomatic men. MATERIALS AND METHODS: We performed a post-hoc analysis of REDUCE in 3,060 "asymptomatic" men with baseline International Prostate Symptom Score (IPSS) <8 and in 2,198 symptomatic men with baseline IPSS ≥8 not taking α-blockers or 5α-reductase inhibitors. We used multivariable Cox regression models to assess associations between statin use at baseline and LUTS incidence and progression. Among asymptomatic men, incident LUTS was defined as the first reported medical or surgical treatment for BPH or sustained clinically significant LUTS (2 reports of IPSS >14). Among symptomatic men, LUTS progression was defined as IPSS increase ≥4 points from baseline, any surgical procedure for BPH, or initiation of a BPH drug. RESULTS: Among asymptomatic and symptomatic men, 550 (18%) and 392 (18%) used statins at baseline, respectively. On multivariable analysis, statin use was not associated with LUTS incidence (HR 1.05; 95% CI 0.78-1.41, p=0.74) in asymptomatic men, or with LUTS progression (HR 1.13; 95% CI 0.96-1.33, p=0.15) in symptomatic men. Similar results were seen in the dutasteride and placebo arms when stratified by treatment assignment. CONCLUSIONS: In REDUCE, statin use was not associated with either incident LUTS in asymptomatic men or LUTS progression in symptomatic men. These data do not support a role for statins in LUTS prevention or management.


Assuntos
Dutasterida/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Sintomas do Trato Urinário Inferior/epidemiologia , Hiperplasia Prostática/tratamento farmacológico , Neoplasias da Próstata/epidemiologia , Idoso , Doenças Assintomáticas/terapia , Progressão da Doença , Método Duplo-Cego , Humanos , Incidência , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/prevenção & controle , Masculino , Pessoa de Meia-Idade , Próstata/efeitos dos fármacos , Próstata/patologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/prevenção & controle , Resultado do Tratamento
8.
Adv Mater ; : e2208573, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460018

RESUMO

Interest in defect engineering for lithium-ion battery (LIB) materials has been sparked by its ability to tailor electrical conductivity and introduce extra active sites for electrochemical reactions. However, harvesting excessive intrinsic defects in the bulk of the electrodes rather than near their surface remains a long-standing challenge. Here we demonstrate a versatile strategy of quenching, which is exercised in lithium titanate (Li4 Ti5 O12 , LTO), a renowned anode for LIBs, to achieve off-stoichiometry in the interior region. In-situ synchrotron analysis and atomic-resolution microscopy reveal the enriched oxygen vacancies and cation redistribution after ice-water quenching, which can facilitate the native unextractable Li ions to participate in reversible cycling. The fabricated LTO anode delivers a sustained capacity of 202 mAh g-1 in the 1.0-2.5 V range with excellent rate capability, and overcomes the poor cycling stability seen in conventional defective electrodes. We also demonstrate the feasibility of tuning the degree of structural defectiveness via quenching agents, which can open up an intriguing avenue of research to harness the intrinsic defects for improving the energy density of rechargeable batteries. This article is protected by copyright. All rights reserved.

9.
JACS Au ; 2(11): 2453-2459, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36465540

RESUMO

Noble metal based nanozymes show great potential in replacing natural enzymes; however, their development is greatly restricted by their relatively low specificity and activity. Herein, we report the synthesis of a class of amorphous/crystalline PtRuTe nanomaterials with a Pt/Te-enriched core and a Ru-enriched shell as efficient peroxidase mimics with selectively enhanced peroxidase-like activity and suppressed oxidase-like activity. We demonstrate that amorphous domains play a critical role in tuning and optimizing the catalytic properties. The PtRuTe nanozyme with high-percentage defects exhibits superior catalytic activities and kinetics, and the suppressed oxidase-like activity could diminish the interference of O2 in the glucose colorimetric assay. The high catalytic performance can be caused by amorphous phase induced electron redistribution and electronic interactions between different elements and the synergistic effect of multimetallic nanocrystals. The concurrent extraordinary peroxidase-like activity and suppressed oxidase-like activity guarantee the amorphous/crystalline PtRuTe nanozymes as promising alternatives of natural enzymes for biosensing and beyond.

10.
Small ; : e2203838, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36511178

RESUMO

To solve surface carrier recombination and sluggish water oxidation kinetics of hematite (α-Fe2 O3 ) photoanodes, herein, an attractive surface modification strategy is developed to successively deposit ultrathin CoOx overlayer and Ni single atoms on titanium (Ti)-doped α-Fe2 O3 (Ti:Fe2 O3 ) nanorods through a two-step atomic layer deposition (ALD) and photodeposition process. The collaborative decoration of ultrathin CoOx overlayer and Ni single atoms can trigger a big boost in photo-electrochemical (PEC) performance for water splitting over the obtained Ti:Fe2 O3 /CoOx /Ni photoanode, with the photocurrent density reaching 1.05 mA cm-2 at 1.23 V vs. reversible hydrogen electrode (RHE), more than three times that of Ti:Fe2 O3 (0.326 mA cm-2 ). Electrochemical and electronic investigations reveal that the surface passivation effect of ultrathin CoOx overlayer can reduce surface carrier recombination, while the catalysis effect of Ni single atoms can accelerate water oxidation kinetics. Moreover, theoretical calculations evidence that the synergy of ultrathin CoOx overlayer and Ni single atoms can lower the adsorption free energy of OH* intermediates and relieve the potential-determining step (PDS) for oxygen evolution reaction (OER). This work provides an exemplary modification through rational engineering of surface electrochemical and electronic properties for the improved PEC performances, which can be applied in other metal oxide semiconductors as well.

11.
Nanomaterials (Basel) ; 12(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500879

RESUMO

In this work, the atomic level doping of Sn into Ga2O3 films was successfully deposited by using a plasma-enhanced atomic layer deposition method. Here, we systematically studied the changes in the chemical state, microstructure evolution, optical properties, energy band alignment, and electrical properties for various configurations of the Sn-doped Ga2O3 films. The results indicated that all the films have high transparency with an average transmittance of above 90% over ultraviolet and visible light wavelengths. X-ray reflectivity and spectroscopic ellipsometry measurement indicated that the Sn doping level affects the density, refractive index, and extinction coefficient. In particular, the chemical microstructure and energy band structure for the Sn-doped Ga2O3 films were analyzed and discussed in detail. With an increase in the Sn content, the ratio of Sn-O bonding increases, but by contrast, the proportion of the oxygen vacancies decreases. The reduction in the oxygen vacancy content leads to an increase in the valence band maximum, but the energy bandgap decreases from 4.73 to 4.31 eV. Moreover, with the increase in Sn content, the breakdown mode transformed the hard breakdown into the soft breakdown. The C-V characteristics proved that the Sn-doped Ga2O3 films have large permittivity. These studies offer a foundation and a systematical analysis for assisting the design and application of Ga2O3 film-based transparent devices.

12.
Chem Sci ; 13(47): 14063-14069, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36540827

RESUMO

Aerobic oxidative desulfurization (AODS) promises a sustainable alternative technology for diesel desulfurization, which necessitates the efficient aerobic oxidation of thiophenic sulfides under mild conditions to minimize energy input, yet being longstandingly plagued by the grand challenge in low-temperature activation of triplet oxygen. Here we synthesize vanadium nitride quantum dots on graphene to controllably create coordination-unsaturated edge/corner V sites for boosting the AODS reaction. The catalyst activates the reaction at 70 °C, and is two orders of magnitude more active than the best V-based catalysts. We demonstrate through computational studies that the low-coordinated edge/corner V sites can effectively activate oxygen and adsorb sulfides to lower the activation barrier, dramatically enhancing the activity. The catalyst achieves deep AODS of real diesel at 80 °C with negligible attenuation in successive reuses, which highlights its attractive industrial potential. These findings provide scientific and practical insights to develop high-performance catalysts for a sustainable AODS process.

13.
Sci Bull (Beijing) ; 67(5): 520-528, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36546173

RESUMO

Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen. A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to significantly boost the photocatalytic activity, but is yet to be realized. Herein, we find that cobalt salt added in the ionothermal synthesis can promote the phase transition of heptazine-based crystalline carbon nitride (CCN) to triazine-based poly(triazine imide) (PTI), rendering the creation of single-atom cobalt coordinated isotype CCN/PTI heterojunction. Co-CCN/PTI exhibits an appreciable apparent quantum yield of 20.88% at 425 nm for photocatalytic hydrogen production with a rate achieving 3538 µmol h-1 g-1 (λ > 420 nm), which is 4.8 times that of CCN and 27.6 times that of PTI. The high photocatalytic activity is attributed to the Type II isotype highly-crystallized CCN/PTI heterojunction for promoting charge carrier migration, and the single-atom Co sites for accelerating surface oxidation reaction.

14.
Adv Mater ; : e2207353, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36479745

RESUMO

Ferromagnetic metals show great prospects in ultralow-power-consumption spintronic devices, due to their high Curie temperature and robust magnetization. However, there is still a lack of reliable solutions for giant and reversible voltage control of magnetism in ferromagnetic metal films. Here, a novel space-charge approach is proposed which allows for achieving a modulation of 30.3 emu/g under 1.3 V in Co/TiO2 multilayer granular films. The robust endurance with more than 5000 cycles is demonstrated. Similar phenomena exist in Ni/TiO2 and Fe/TiO2 multilayer granular films, which shows its universality. The magnetic change of 107% in Ni/TiO2 underlines its potential in a voltage-driven ON-OFF magnetism. Such giant and reversible voltage control of magnetism can be ascribed to space-charge effect at the ferromagnetic metals/TiO2 interfaces, in which spin-polarized electrons are injected into the ferromagnetic metal layer with the adsorption of lithium-ions on the TiO2 surface. These results open the door for a promising method to modulate the magnetization in ferromagnetic metals, paving the way toward the development of ionic-magnetic-electric coupled applications.

15.
Angew Chem Int Ed Engl ; : e202216898, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36539374

RESUMO

Physical properties of materials are mainly determined by valence electron configurations, where different valence shells would induce divergent phenomena. In compounds containing Sc2+ , 3d electron occupancy is expected, the same as other transition metal atoms like Ti3+ . But this situation still awaits experimental verification in inorganic materials. Here, we selected ScS to measure the valence electron density and orbital population of Sc2+ through delicate quantitative convergent-beam electron diffraction. With the absence of 3d orbital features around Sc-atom sites and the nearly bare population of t2g orbital, the unintuitive occupation of 4s orbital in Sc2+ is concluded. It should be the first time to report such a special electron configuration in a transition metal compound, in which 4s rather than 3d orbital is preferred. Our findings reveal the distinct behavior of Sc and probable ways to modulate material properties by controlling electron orbitals.

16.
Int J Nanomedicine ; 17: 5209-5227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388877

RESUMO

Triple-negative breast cancer (TNBC) exhibits high recurrence and mortality rates because of the lack of effective treatment targets. Surgery and traditional chemotherapy are the primary treatment options. Immunotherapy shows high potential for treating various cancers but exhibits limited efficacy against TNBC as a monotherapy. Chemoimmunotherapy has broad prospects for applications for cancer treatment conferred through the synergistic immunomodulatory and anti-tumor effects of chemotherapy and immunotherapeutic strategies. However, improving the efficacy of synergistic therapy and reducing the side effects of multiple drugs remain to be the main challenges in chemoimmunotherapy against TNBC. Nanocarriers can target both cancer and immune cells, promote drug accumulation, and show minimal toxicity, making them ideal delivery systems for chemotherapeutic and immunotherapeutic agents. In this review, we introduce the immunomodulatory effects of chemotherapy and combined mechanisms of chemoimmunotherapy, followed by a summary of nanoparticle-mediated chemoimmunotherapeutic strategies used for treating TNBC. This up-to-date synthesis of relevant findings in the field merits contemplation, while considering avenues of investigation to enable advances in the field.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Imunoterapia
17.
J Am Chem Soc ; 144(48): 21908-21915, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36419236

RESUMO

From spanning bulks to nanoclusters, surface-enhanced Raman scattering (SERS) substrates of noble metals have frequently been explored for a long time. However, further downsizing nanoclusters to the atomic level, the surface plasmon resonance effect disappears, making the research on the SERS effect of atom-scale noble metal still lacking. Here, we discover a single-atom enhanced Raman scattering (SAERS) effect based on Au single atoms anchored on amorphous C3N4 nanosheets (Au1/ACNs). The Au1/ACN exhibits an excellent spectral stability and reproducibility, as the uniform dispersed Au single atoms avoid the agglomeration of Au atoms to generate nonuniformly dispersed "hotspots" that suffer from poor SERS stability and reproducibility. Even only ∼2.5% Au-coated area in the laser illuminated area can yield an enhancement factor of 2.5 × 104. The SAERS effect is attributed to the synergistic effect of Au single atoms anchored on amorphous C3N4, which increases the dipole moment and polarizability of molecules, enhancing the Raman signal of probe molecules. Furthermore, we propose a novel single-atom charge transfer mechanism that single-atom Au dominates higher electron delocalizability and higher electronic density of states near the HOMO level than the Au cluster. Our results will erect a new milepost for the application of single-atom materials in the field of enhanced Raman spectroscopy.

18.
BMC Bioinformatics ; 23(1): 456, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36324073

RESUMO

BACKGROUND: Ligand-protein interactions play a key role in defining protein function, and detecting natural ligands for a given protein is thus a very important bioengineering task. In particular, with the rapid development of AI-based structure prediction algorithms, batch structural models with high reliability and accuracy can be obtained at low cost, giving rise to the urgent requirement for the prediction of natural ligands based on protein structures. In recent years, although several structure-based methods have been developed to predict ligand-binding pockets and ligand-binding sites, accurate and rapid methods are still lacking, especially for the prediction of ligand-binding regions and the spatial extension of ligands in the pockets. RESULTS: In this paper, we proposed a multilayer dynamics perturbation analysis (MDPA) method for predicting ligand-binding regions based solely on protein structure, which is an extended version of our previously developed fast dynamic perturbation analysis (FDPA) method. In MDPA/FDPA, ligand binding tends to occur in regions that cause large changes in protein conformational dynamics. MDPA, examined using a standard validation dataset of ligand-protein complexes, yielded an averaged ligand-binding site prediction Matthews coefficient of 0.40, with a prediction precision of at least 50% for 71% of the cases. In particular, for 80% of the cases, the predicted ligand-binding region overlaps the natural ligand by at least 50%. The method was also compared with other state-of-the-art structure-based methods. CONCLUSIONS: MDPA is a structure-based method to detect ligand-binding regions on protein surface. Our calculations suggested that a range of spaces inside the protein pockets has subtle interactions with the protein, which can significantly impact on the overall dynamics of the protein. This work provides a valuable tool as a starting point upon which further docking and analysis methods can be used for natural ligand detection in protein functional annotation. The source code of MDPA method is freely available at: https://github.com/mingdengming/mdpa .


Assuntos
Algoritmos , Proteínas , Ligantes , Ligação Proteica , Reprodutibilidade dos Testes , Sítios de Ligação , Conformação Proteica , Proteínas/química
19.
Nanomicro Lett ; 14(1): 223, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36374377

RESUMO

Despite of suitable band structures for harvesting solar light and driving water redox reactions, polymeric carbon nitride (PCN) has suffered from poor charge transfer ability and sluggish surface reaction kinetics, which limit its photocatalytic activity for water splitting. Herein, atomically dispersed Zn-coordinated three-dimensional (3D) sponge-like PCN (Zn-PCN) is synthesized through a novel intermediate coordination strategy. Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N6 configuration featured with an electron-deficient state. Such an electronic configuration has been demonstrated contributive to promoted electron excitation, accelerated charge separation and transfer as well as reduced water redox barriers. Further benefited from the abundant surface active sites derived from the 3D porous structure, Zn-PCN realizes visible-light photocatalysis for overall water splitting with H2 and O2 simultaneously evolved at a stoichiometric ratio of 2:1. This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.

20.
Nano Lett ; 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36410727

RESUMO

The insight into the three-dimensional configuration of ferroelectric ordering in ferroelectric nanomaterials is motivated by the application of the development of functional nanodevices and the structural designing. However, the atomic deciphering of the spatial distribution of ordered structure remains challenging for the limitation of dimension and probing techniques. In this paper, a neutron pair distribution function (nPDF) was utilized to analyze the spontaneous polarization distribution of zero-dimensional PbTiO3 nanoparticles in three dimensions, via the application of reverse Monte Carlo (RMC) modeling. The comprehensive identification with transmission electron microscopy verified the linear characteristics of polarization along the c-axis in the main body, while electric polarization distribution on the surface was enhanced abnormally. In addition, the correlation of dipole vectors extending to three unit cells below the surface is retained. This work shows an application of the micro/macroscale information to effectively decode the polarization structure of nanoferroelectrics, providing new views of designing nanoferroelectric devices.

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