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The well known trade-off between hardness and toughness (resistance to fracture) makes simultaneous improvement of both properties challenging, especially in diamond. The hardness of diamond can be increased through nanostructuring strategies1,2, among which the formation of high-density nanoscale twins - crystalline regions related by symmetry - also toughens diamond2. In materials other than diamond, there are several other promising approaches to enhancing toughness in addition to nanotwinning3, such as bio-inspired laminated composite toughening4-7, transformation toughening8 and dual-phase toughening9, but there has been little research into such approaches in diamond. Here we report the structural characterization of a diamond composite hierarchically assembled with coherently interfaced diamond polytypes (different stacking sequences), interwoven nanotwins and interlocked nanograins. The architecture of the composite enhances toughness more than nanotwinning alone, without sacrificing hardness. Single-edge notched beam tests yield a toughness up to five times that of synthetic diamond10, even greater than that of magnesium alloys. When fracture occurs, a crack propagates through diamond nanotwins of the 3C (cubic) polytype along {111} planes, via a zigzag path. As the crack encounters regions of non-3C polytypes, its propagation is diffused into sinuous fractures, with local transformation into 3C diamond near the fracture surfaces. Both processes dissipate strain energy, thereby enhancing toughness. This work could prove useful in making superhard materials and engineering ceramics. By using structural architecture with synergetic effects of hardening and toughening, the trade-off between hardness and toughness may eventually be surmounted.
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Although direct generation of high-value complex molecules and feedstock by coupling of ubiquitous small molecules such as CO2 and N2 holds great appeal as a potential alternative to current fossil-fuel technologies, suitable scalable and efficient catalysts to this end are not currently available as yet to be designed and developed. To this end, here we prepare and characterize SbxBi1-xOy clusters for direct urea synthesis from CO2 and N2 via C-N coupling. The introduction of Sb in the amorphous BiOx clusters changes the adsorption geometry of CO2 on the catalyst from O-connected to C-connected, creating the possibility for the formation of complex products such as urea. The modulated Bi(II) sites can effectively inject electrons into N2, promoting C-N coupling by advantageous modification of the symmetry for the frontier orbitals of CO2 and N2 involved in the rate-determining catalytic step. Compared with BiOx, SbxBi1-xOy clusters result in a lower reaction potential of only -0.3 V vs. RHE, an increased production yield of 307.97 µg h-1 mg-1cat, and a higher Faraday efficiency (10.9%), pointing to the present system as one of the best catalysts for urea synthesis in aqueous systems among those reported so far. Beyond the urea synthesis, the present results introduce and demonstrate unique strategies to modulate the electronic states of main group p-metals toward their use as effective catalysts for multistep electroreduction reactions requiring C-N coupling.
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Component modulation endows Mn-based electrodes with prominent energy storage properties due to their adjustable crystal structure characteristics. Herein, ZnMn2(PO4)2·nH2O (ZMP·nH2O) was obtained by a hydration reaction from ZnMn2(PO4)2 (ZMP) during an electrode-aging evolution. Benefiting from the introduction of lattice H2O molecules into the ZMP structure, the ion transmission path has been expanded along with the extended d-spacing, which will further facilitate the ZMP â ZMP·nH2O phase evolution and electrochemical reaction kinetics. Meanwhile, the hydrogen bond can be generated between H2O and O in PO43-, which strengthens the structure stability of ZMP·nH2O and lowers the conversion barrier from ZMP to ZMP·4H2O during the Zn2+ uptake/removal process. Thereof, ZMP·nH2O delivers enhanced electrochemical reaction kinetics with robust structure tolerance (106.52 mA h g-1 at 100 mA g-1 over 620 cycles). This high-energy aqueous Zn||ZMP·nH2O battery provides a facile strategy for engineering and exploration of high-performance ZIBs to realize the practical application of Mn-based cathodes.
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Oxygen vacancies are generally considered to play a crucial role in the oxygen evolution reaction (OER). However, the generation of active sites created by oxygen vacancies is inevitably restricted by their condensation and elimination reactions. To overcome this limitation, here, we demonstrate a novel photoelectric reconstruction strategy to incorporate atomically dispersed Cu into ultrathin (about 2-3 molecular) amorphous oxyhydroxide (a-CuM, M = Co, Ni, Fe, or Zn), facilitating deprotonation of the reconstructed oxyhydroxide to generate high-valence Cu. The in situ XAFS results and first-principles calculations reveal that Cu atoms are stabilized at high valence during the OER process due to Jahn-Teller distortion, resulting in para-type double oxygen vacancies as dynamically stable catalytic sites. The optimal a-CuCo catalyst exhibits a record-high mass activity of 3404.7 A g-1 at an overpotential of 300 mV, superior to the benchmarking hydroxide and oxide catalysts. The developed photoelectric reconstruction strategy opens up a new pathway to construct in situ stable oxygen vacancies by high-valence Cu single sites, which extends the design rules for creating dynamically stable active sites.
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Glioblastoma is the most fatal and insidious malignancy, due to the existence of the blood-brain barrier (BBB) and the high invasiveness of tumor cells. Abnormal mitochondrial viscosity has been identified as a key feature of malignancies. Therefore, this study reports on a novel fluorescent probe for mitochondrial viscosity, called ZVGQ, which is based on the twisted intramolecular charge transfer (TICT) effect. The probe uses 3-dicyanomethyl-1,5,5-trimethylcyclohexene as an electron donor moiety and molecular rotor, and triphenylphosphine (TPP) cation as an electron acceptor and mitochondrial targeting group. ZVGQ is highly selective, pH and time stable, and exhibits rapid viscosity responsiveness. In vitro experiments showed that ZVGQ could rapidly recognize to detect the changes in mitochondrial viscosity induced by nystatin and rotenone in U87MG cells and enable long-term imaging for up to 12 h in live U87MG cells. Additionally, in vitro 3D tumor spheres and in vivo orthotopic tumor-bearing models demonstrated that the probe ZVGQ exhibited exceptional tissue penetration depth and the ability to penetrate the BBB. The probe ZVGQ not only successfully visualizes abnormal mitochondrial viscosity changes, but also provides a practical and feasible tool for real-time imaging and clinical diagnosis of glioblastoma.
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Colorantes Fluorescentes , Glioblastoma , Mitocondrias , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Humanos , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Mitocondrias/metabolismo , Viscosidad , Línea Celular Tumoral , Animales , Ratones , Ratones Desnudos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Imagen ÓpticaRESUMEN
Copper is a critical element in both human and animal metabolic processes. Its role includes supporting connective tissue cross-linking, as well as iron and lipid metabolism; at the same time, copper is also a toxic heavy metal that can cause harm to both the environment and human health. Glutathione (GSH) is a tripeptide composed of glutamic acid, cysteine, and glycine combined with sulfhydryl groups. Its properties include acting as an antioxidant and facilitating integrative detoxification. GSH is present in both plant and animal cells and has a fundamental role in maintaining living organisms. GSH is the most abundant thiol antioxidant in the human body. It exists in reduced and oxidized forms within cells and provides significant biochemical functions, such as regulating vitamins such as vitamins D, E, and C, and facilitating detoxification. A fluorescent probe has been developed to detect copper ions selectively, sensitively, and rapidly. This report outlines the successful work on creating a peptide probe, TGN (TPE-Trp-Pro-Gly-Cln-His-NH2 ), with specific Cu2+ detection capabilities, and a significant fluorescence recovery occurred with the addition of GSH. This indicates that the probe can detect Cu2+ and GSH concurrently. The detection limit for Cu2+ in the buffer solution was 264 nM (R2 = 0.9992), and the detection limit for GSH using the TGN-Cu2+ complex was 919 nM (R2 = 0.9917). The probe exhibits high cell permeability and low biotoxicity that make it ideal for live cell imaging in biological conditions. This peptide probe has the capability to detect Cu2+ and GSH in biological cells.
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Antioxidantes , Cobre , Animales , Humanos , Cobre/química , Ligandos , Glutatión , Péptidos/química , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos , VitaminasRESUMEN
In consideration of high specific capacity and low redox potential, lithium metal anodes have attracted extensive attention. However, the cycling performance of lithium metal batteries generally deteriorates significantly under the stringent conditions of high temperature due to inferior heat tolerance of the solid electrolyte interphase (SEI). Herein, controllable SEI nanostructures with excellent thermal stability are established by the (trifluoromethyl)trimethylsilane (TMSCF3 )-induced interface engineering. First, the TMSCF3 regulates the electrolyte decomposition, thus generating an SEI with a large amount of LiF, Li3 N, and Li2 S nanocrystals incorporated. More importantly, the uniform distributed nanocrystals have endowed the SEI with enhanced thermostability according to the density functional theory simulations. Particularly, the sub-angstrom visualization on SEI through a conventional transmission electron microscope (TEM) is realized for the first time and the enhanced tolerance to the heat damage originating from TEM imaging demonstrates the ultrahigh thermostability of SEI. As a result, the highly thermostable interphase facilitates a substantially prolonged lifespan of full cells at a high temperature of 70 °C. As such, this work might inspire the universal interphase design for high-energy alkali-metal-based batteries applicated in a high-temperature environment.
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Cysteine (Cys), a small-molecule biothiol, has recently been identified as a novel Glioblastoma (GBM) biomarker. The highly selective real-time monitoring and fluorescence imaging of Cys levels in vivo is of great significance for the early diagnosis and treatment of GBM. In this work, we reported a highly selective Cys fluorescent probe ZS-C1, based on quinoline according to the mechanism of the conjugate addition cyclization reaction. The Limit of Detection (LOD) of probe ZS-C1 was 1.97 µM, λex = 380 nm; λem = 531 nm. In vitro experiments showed that ZS-C1 could be distinguished from Hcy and GSH significantly, and the fluorescence quantum yield was reduced by 30 times. Further, biological imaging and 3D tumor sphere penetration assay showed that the ZS-C1 could monitor both exogenous and endogenous Cys in the living U87MG cells, and the fluorescence of probe ZS-C1 diffusely distributed inside the U87MG three-dimensional solid cell spheroid (up to 60 µM deep into the solid tumors). This work provided a potential tool for further investigations of Cys in biological samples and critical information for early diagnosis of glioma and guidance for clinical surgery.
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Glioma , Quinolinas , Cisteína , Colorantes Fluorescentes , Glioma/diagnóstico por imagen , Glutatión , Células HeLa , Homocisteína , HumanosRESUMEN
As a precursor of all reactive oxygen species (ROS), superoxide anions play an important role in organisms. However, excessive superoxide anions can cause various diseases. Thus, it is highly urgent to develop efficient tools for in situ superoxide anion detection. In this work, a novel boric acid-based, mitochondria-targeted fluorescent probe Mito-YX for superoxide anion detection was designed by regulating its intramolecular charge transfer (ICT) effect. The probe exhibited turn-on fluorescence enhancement within 4 min of reaction with the superoxide anion. In addition, Mito-YX also exhibited high selectivity and a low detection limit down to 0.24 µM with good mitochondrial targeting characteristics, which provided a necessary basis for in vivo detection of superoxide anions. What is more, Mito-YX was successfully applied for the in situ monitoring of superoxide anions in living MCF-7 cells, RAW 264.7 cells and a mouse model of lung inflammation stimulated by LPS. This work provided an important and promising tool for rapid in situ diagnosis and research of the progression of pneumonia.
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Colorantes Fluorescentes , Superóxidos , Animales , Colorantes Fluorescentes/toxicidad , Humanos , Células MCF-7 , Ratones , Mitocondrias , Imagen ÓpticaRESUMEN
Most of the ONOO- fluorescent probes have restricted applications because of their aggregation-caused quenching (ACQ) effect, long response time and low fluorescence enhancement. Herein, we developed a novel AIEgen fluorescent probe (PE-XY) based on a benzothiazole and quinolin scaffold with high sensitivity and selectivity for imaging of ONOO-. The results indicated that probe PE-XY exhibited fast response towards ONOO- with 2000-fold enhancement of fluorescence intensity ratio in vitro. Moreover, PE-XY exhibited a relatively high sensitivity (limit of detection: 8.58 nM), rapid response (<50 s), high fluorescence quantum yield (δ = 0.81) and excellent selectivity over other analytes towards ONOO-in vitro. Furthermore, PE-XY was successfully applied to detect endogenous ONOO- levels in living HeLa cells, C. elegans and inflammatory mice with low cytotoxicity. Overall, this work provided a novel fast-response and highly selective AIEgen fluorescent probe for real-time monitoring ONOO- fluctuations in living systems.
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Colorantes Fluorescentes , Ácido Peroxinitroso , Animales , Caenorhabditis elegans , Fluorescencia , Colorantes Fluorescentes/toxicidad , Células HeLa , Humanos , Ratones , Ácido Peroxinitroso/toxicidadRESUMEN
Although supercapacitors have attracted more and more attention owing to their fast charging speed and high power density, their wide applications have still been limited by their low energy density. In this study, a new CuS-nanoparticle-decorated Ti3C2Txelectrode material is fabricated via a facilein situsynthesis strategy at room temperature. CuS nanoparticles, generated from thein situreaction of Cu (NO3)2·3H2O with Na2S·9H2O, are anchored between the Ti3C2Txinterlayers through electrostatic interaction. This type of structural construction is found capable of not only reducing the surface oxidation of Ti3C2Tx, but also preventing the accumulation of CuS nanoparticles by the template effect of Ti3C2Txnanoplates. As a result, the CuS/Ti3C2Txnanohybrid delivers a maximum specific capacitance of 911 F g-1at 1 A g-1and a good cycling stability. A symmetric supercapacitor fabricated using the CuS/Ti3C2Txnanohybrid as the electrode material exhibits an energy density of 43.56 W h kg-1with a power density of 475 W kg-1. Consequently, this work provides a new perspective of microstructural design for the preparation of electrode materials with superhigh specific capacitance through an easy and low-costin situ-reaction method at room temperature.
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AIMS OF THE STUDY: Blood coagulation parameters are colossally important for clinical evaluation of palliative chemotherapy; however, this niche was not explored earlier for advanced-stage non-small cell lung cancer (NSCLC). Study focuses to explore the clinical relevancy of Coagulation parameters; prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (FIB), D-dimer and international normalised ratio (INR) and their response to palliative chemotherapy in advanced-stage NSCLC. METHODS: A retrospective study was conducted between 2013 and 2019 in Jiangsu Cancer hospital, Nanjing, PR. China. Medical records of 5445 patients were succinctly reviewed and classified accordingly to the inclusion and exclusion criteria. A total of 216 advanced NSCLC patients who used a first-line chemotherapy and antiangiogenic therapy regimen were enrolled in this study under ethical approval (JSCH-2020C-009). Blood samples were collected from these patients to measure the response levels of these coagulation parameters at time of admission to hospital and at the beginning of 4 cycles of Palliative therapy. We find the clinical value of all these coagulation parameters by using SPSS 24. Univariate Cox regression and Multivariate Cox regression models were used to identify the factors that were associated with progression-free survival (PFS) and the response to palliative chemotherapy. RESULTS: In the Kaplan-Meier survival analysis for overall median (95% CI) survival of high pre-treatment coagulation parameters showed shorter PFS compared with normal pre-treatment except TT and their overall median (95% CI) follow-up was 3.3 (3.12-3.47). Coagulation parameters have showed clinical relevance as a potential independent prognostic factor of PFS in the Univariate Cox regression. In multivariable model, Age (≥60 years vs < 60 years), cancer differentiation (Unknown vs Poor), PT (High vs Normal) range, FIB (High vs Normal) range and D-dimer (High vs Normal) range, (P = .025, P = .045, P = .029, P = .049 and P = .011, respectively) were associated as a prognostic factor of PFS in NSCLC. Patients on 3-drugs regimen found to have better PFS compared with the ones taking the 2-drugs treatment regimen (P = .043). CONCLUSION: The high range of PT, FIB and D-dimers was associated with poor prognosis of advanced-stage NSCLC. Our findings also confirmed that patients on 3-drugs regimen showed longer PFS compared with 2-drugs regimen.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Preparaciones Farmacéuticas , Coagulación Sanguínea , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , China , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Persona de Mediana Edad , Cuidados Paliativos , Plasma , Pronóstico , Estudios RetrospectivosRESUMEN
Two-dimensional material indium selenide (InSe) has offered a new platform for fundamental research in virtue of its emerging fascinating properties. Unlike 2H-phase transition-metal dichalcogenides (TMDs), ε phase InSe with a hexagonal unit cell possesses broken inversion symmetry in all the layer numbers, and predicted to have a strong second harmonic generation (SHG) effect. In this work, we find that the as-prepared pure InSe, alloyed InSe1- xTe x and InSe1- xS x ( x = 0.1 and 0.2) are ε phase structures and exhibit excellent SHG performance from few-layer to bulk-like dimension. This high SHG efficiency is attributed to the noncentrosymmetric crystal structure of the ε-InSe system, which has been clearly verified by aberration-corrected scanning transmission electron microscopy (STEM) images. The experimental results show that the SHG intensities from multilayer pure ε-InSe and alloyed InSe0.9Te0.1 and InSe1- xS x ( x = 0.1 and 0.2) are around 1-2 orders of magnitude higher than that of the monolayer TMD systems and even superior to that of GaSe with the same thickness. The estimated nonlinear susceptibility χ(2) of ε-InSe is larger than that of ε-GaSe and monolayer TMDs. Our study provides first-hand information about the phase identification of ε-InSe and indicates an excellent candidate for nonlinear optical (NLO) applications as well as the possibility of engineering SHG response by alloying.
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Achieving large-sized and thinly layered 2D metal phosphorus trichalcogenides with high quality and yield has been an urgent quest due to extraordinary physical/chemical characteristics for multiple applications. Nevertheless, current preparation methodologies suffer from uncontrolled thicknesses, uneven morphologies and area distributions, long processing times, and inferior quality. Here, a sonication-free and fast (in minutes) electrochemical cathodic exfoliation approach is reported that can prepare large-sized (typically ≈150 µm2 ) and thinly layered (≈70% monolayer) NiPS3 flakes with high crystallinity and pure phase structure with a yield ≈80%. During the electrochemical exfoliation process, the tetra-n-butylammonium salt with a large ionic diameter is decomposed into gaseous species after the intercalation and efficiently expands the tightly stratified bulk NiPS3 crystals, as revealed by in situ and ex situ characterizations. Atomically thin NiPS3 flakes can be obtained by slight manual shaking rather than sonication, which largely preserves in-plane structural integrity with large size and minimum damage. The obtained high quality NiPS3 offers a new and ideal model for overall water splitting due to its inherent fully exposed S and P atoms that are often the active sites for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Consequently, the bifunctional NiPS3 exhibits outstanding performance for overall water splitting.
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Twenty-four 1,2-diarylbenzimidazole derivatives were designed, synthesized and biologically evaluated. It turned out that most of them were potential anticancer drugs. Among them, compound c24 showed the highest anti-tumor activity (GI50â¯=â¯0.71-2.41⯵M against HeLa, HepG2, A549 and MCF-7 cells), and low toxicity to normal cells (CC50â¯>â¯100⯵M against L02 cells). In the microtubule binding assay, c24 showed the most potent inhibition of microtubule polymerization (IC50â¯=â¯8.47⯵M). The binding ability of compound c24 to tubulin crystal was verified by molecular docking simulation experiment. Further studies on HepG2 and HeLa cells showed that compound c24 could cause mitotic arrest of tumor cells to G2/M phase then inducing apoptosis. To sum up, compound c24 is a promising microtubule assembly inhibitor.
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Antineoplásicos/farmacología , Bencimidazoles/farmacología , Simulación del Acoplamiento Molecular , Moduladores de Tubulina/farmacología , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Bencimidazoles/síntesis química , Bencimidazoles/química , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Polimerizacion/efectos de los fármacos , Relación Estructura-Actividad Cuantitativa , Especies Reactivas de Oxígeno/análisis , Especies Reactivas de Oxígeno/metabolismo , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/químicaRESUMEN
Cyclooxygenase-2 (COX-2) as a rate-limiting metabolism enzyme of arachidonic acid has been found to be implicated in tumor occurrence, angiogenesis, metastasis as well as apoptosis inhibition, regarded as an attractive therapeutic target for cancer therapy. In our research, a series of dihydropyrazole derivatives containing benzo oxygen heterocycle and sulfonamide moieties were designed as highly potent and selective COX-2 inhibitors by computer-aided drug analysis of known COX-2 inhibitors. A total of 26 compounds were synthesized and evaluated COX-2 inhibition and pharmacological efficiency both in vitro and in vivo with multi-angle of view. Among them, compound 4b exhibited most excellent anti-proliferation activities against SW620 cells with IC50 of 0.86 ± 0.02 µM than Celecoxib (IC50 = 1.29 ± 0.04 µM). The results favored our rational design intention and provides compound 4b as an effective COX-2 inhibitor available for the development of colon tumor therapeutics.
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Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/farmacología , Diseño de Fármacos , Oxígeno/química , Pirazoles/química , Pirazoles/farmacología , Sulfonamidas/química , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon , Inhibidores de la Ciclooxigenasa 2/síntesis química , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Conformación Molecular , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Pirazoles/síntesis química , Relación Estructura-Actividad Cuantitativa , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Two-dimensional (2D) gallium nitride (GaN) has been highly anticipated because its quantum confinement effect enables desirable deep-ultraviolet emission, excitonic effect and electronic transport properties. However, the currently obtained 2D GaN can only exist as intercalated layers of atomically thin quantum wells or nanometer-scale islands, limiting further exploration of its intrinsic characteristics. Here, we report, for the first time, the growth of micrometer-sized 2D GaN single crystals on liquid metals via a surface-confined nitridation reaction and demonstrate that the 2D GaN shows uniformly incremental lattice, unique phonon modes, blue-shifted photoluminescence emission and improved internal quantum efficiency, providing direct evidence to the previous theoretical predictions. The as-grown 2D GaN exhibits an electronic mobility of 160 cm2·V-1·s-1. These findings pave the way to potential optoelectronic applications of 2D GaN single crystals.
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Dihydropteroate synthase (DHPS) is an enzyme of the folate biosynthesis pathway, which catalyzes the formation of 7,8-dihydropteroate (DHPt) from 6-hydroxymethyl-7,8-dihydropterin pyrophosphate (DHPPP) and para-aminobenzoic acid (pABA). DHPS is the long-standing target of the sulfonamide class of antibiotics that compete with pABA. In the wake of sulfa drug resistance, targeting the structurally rigid (and more conserved) pterin site has been proposed as an alternate strategy to inhibit DHPS in wild-type and sulfa drug resistant strains. Following the work on developing pterin-site inhibitors of the adjacent enzyme 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK), we now present derivatives of 8-mercaptoguanine, a fragment that binds weakly within both enzymes, and quantify sub-µm binding using surface plasmon resonance (SPR) to Escherichia coli DHPS (EcDHPS). Eleven ligand-bound EcDHPS crystal structures delineate the structure-activity relationship observed providing a structural framework for the rational development of novel, substrate-envelope-compliant DHPS inhibitors.
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Dihidropteroato Sintasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Guanina/análogos & derivados , Antibacterianos/química , Antibacterianos/metabolismo , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Dihidropteroato Sintasa/metabolismo , Inhibidores Enzimáticos/metabolismo , Escherichia coli/enzimología , Guanina/metabolismo , Enlace de Hidrógeno , Ligandos , Unión Proteica , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Especificidad por Sustrato , Sulfonamidas/química , Resonancia por Plasmón de SuperficieRESUMEN
With the increasingly acquired resistance, relapse and side effects of known marketed BRAFV600E inhibitors, it's significant to design the more effective and novel drugs. In this study, a series of novel pyrazole derivatives containing acetamide bond had been designed and synthesized on the basis of analysis of the endogenous ligands extracted from the known B-Raf co-crystals in the PDB database. Then, the compounds were evaluated for biological activities as potential BRAFV600E inhibitors. The bioassay results in vitro against three human tumor cell lines revealed that some of the compounds showed very impressed antiproliferative property. Among them, the compound 5r with IC50 values of 0.10⯱â¯0.01⯵M against BRAFV600E and 0.96⯱â¯0.10⯵M against A375 cell line, showed the most potent inhibitory effect, compared with the positive-controlled agents vemurafenib (IC50â¯=â¯0.04⯱â¯0.004⯵M for BRAFV600E, IC50â¯=â¯1.05⯱â¯0.10⯵M against A375). Further investigation confirmed that the compound 5r could induce A375 cell apoptosis, induce A375 cell death through changing mitochondrial membrane potential, and result in A375 cell arrest at the G1 phase of the cell cycle. Docking simulations results indicated that the compound 5r could bind tightly at the BRAFV600E active site. Meanwhile, 3D-QSAR model suggested that these compounds may be potential anticancer inhibitors. Overall, the article provided some new molecular scaffolds for the further BRAFV600E inhibitors.
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Acetamidas/farmacología , Diseño de Fármacos , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Pirazoles/farmacología , Acetamidas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HT29 , Humanos , Modelos Moleculares , Estructura Molecular , Proteínas Proto-Oncogénicas B-raf/metabolismo , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-ActividadRESUMEN
MMP-2/MMP-8 is established as one of the most important metalloenzymes for targeting cancer. A series of dihydropyrazothiazole derivatives (E1-E18) bearing a salicylaldehyde group linked to Pyrazole ring were designed, synthesized, and evaluated for their pharmacological activity as MMP-2/MMP-8 inhibitors. Among them, compound E17 exhibited most potent inhibitory activity (IC50â¯=â¯2.80⯵M for MMP-2 and IC50â¯=â¯5.6⯵M for MMP-8), compared to the positive drug CMT-1 (IC50â¯=â¯1.29⯵M). Compounds (E1-E18) were scrutinized by CoMFA and CoMSIA techniques of Three-dimensional quant. structure-activity relationship (3D-QSAR), as well as a docking simulation. Moreover, treatment with compound E4 could induce MCF-7 cell apoptosis. Overall, the biological profile of E1-E18 may provide a research basis for the development of new agents against cancer.