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1.
Front Oncol ; 14: 1391698, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139287

RESUMEN

In a variety of cancers, immune checkpoint inhibitors (ICIs) have demonstrated substantial survival advantages. Nevertheless, the widespread use of ICIs in the clinic has resulted in a growing interest in immune-related adverse events (irAEs) and their treatment methods. This paper reports a case in which a patient with three sequential severe irAEs was successfully treated. After undergoing two regimens of sintilimab in conjunction with chemotherapy for advanced lung cancer, the patient developed myocarditis combined with hepatitis. Subsequently, the patient developed pneumonia following remission from treatment. We also discuss the mechanism of irAEs, principles of treatment, and progress in the study of biomarkers for early prediction of irAEs by reviewing the literature.

2.
Int Immunopharmacol ; 141: 112915, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39146784

RESUMEN

Cerebral ischemia-reperfusion injury (CI/RI) is a leading cause of disability and mortality worldwide, with limited therapeutic options available. Erianin, a natural compound derived from traditional Chinese medicine, has been reported to possess anti-inflammatory and neuroprotective properties. This study aimed to investigate the therapeutic potential of Erianin in CI/RI and elucidate its underlying mechanisms. Network pharmacology analysis predicted that Erianin could target the PI3K/AKT pathway, which are closely associated with CI/RI. In vivo experiments using a rat model of CI/RI demonstrated that Erianin treatment significantly alleviated neurological deficits, reduced infarct volume, and attenuated neuronal damage. Mechanistically, Erianin inhibited microglial cell polarization towards the pro-inflammatory M1 phenotype, as evidenced by the modulation of specific markers. Furthermore, Erianin suppressed the expression of pro-inflammatory cytokines and mediators, such as TNF-α, IL-6, and COX-2, while enhancing the production of anti-inflammatory factors, including Arg1, CD206, IL-4 and IL-10. In vitro studies using oxygen-glucose deprivation/reoxygenation (OGD/R)-stimulated microglial cells corroborated the anti-inflammatory and anti-apoptotic effects of Erianin. Notably, Erianin inhibited the NF-κB signaling pathway by inhibiting p65 phosphorylation and preventing the nuclear translocation of the p65 subunit. Collectively, these findings suggest that Erianin represents a promising therapeutic candidate for CI/RI by targeting microglial cell polarization and inflammation.

3.
Fitoterapia ; 177: 106142, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39067487

RESUMEN

The investigation of the leaves of Pittosporum elevaticostatum Chang et Yan led to the isolation of fifteen pentacyclic triterpenoids (1-15), including five previously undescribed ones (1-5), and nine others (16-24). The structures of compounds 1-5 were elucidated based on comprehensive spectroscopic techniques, including one dimension (1D) and 2D nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectroscopy (HR-ESI-MS), and other methods. Compounds 2 and 13 demonstrated significant inhibitory activity against Listeria monocytogenes (L. monocytogenes) with minimum inhibitory concentration (MIC) values of 32 µM. Scanning electron microscopy (SEM) observations revealed insights into the antibacterial mechanism, indicating that compounds 2 and 13 either prevent biofilm formation of dispersed the preformed cell membranes. Additionally, compounds 1, 5, 7, and 12 exhibited anti-inflammatory activity on lipopolysaccharide (LPS)-stimulated BV-2 microglial cells with IC50 values ranging from 11.27 to 17.80 µM.


Asunto(s)
Antibacterianos , Antiinflamatorios , Listeria monocytogenes , Pruebas de Sensibilidad Microbiana , Triterpenos Pentacíclicos , Hojas de la Planta , Hojas de la Planta/química , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Estructura Molecular , Ratones , Animales , Listeria monocytogenes/efectos de los fármacos , Triterpenos Pentacíclicos/farmacología , Triterpenos Pentacíclicos/aislamiento & purificación , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Microglía/efectos de los fármacos , Línea Celular , China
4.
Cancer Imaging ; 24(1): 64, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773660

RESUMEN

BACKGROUND: To explore the potential of different quantitative dynamic contrast-enhanced (qDCE)-MRI tracer kinetic (TK) models and qDCE parameters in discriminating benign from malignant soft tissue tumors (STTs). METHODS: This research included 92 patients (41females, 51 males; age range 16-86 years, mean age 51.24 years) with STTs. The qDCE parameters (Ktrans, Kep, Ve, Vp, F, PS, MTT and E) for regions of interest of STTs were estimated by using the following TK models: Tofts (TOFTS), Extended Tofts (EXTOFTS), adiabatic tissue homogeneity (ATH), conventional compartmental (CC), and distributed parameter (DP). We established a comprehensive model combining the morphologic features, time-signal intensity curve shape, and optimal qDCE parameters. The capacities to identify benign and malignant STTs was evaluated using the area under the curve (AUC), degree of accuracy, and the analysis of the decision curve. RESULTS: TOFTS-Ktrans, EXTOFTS-Ktrans, EXTOFTS-Vp, CC-Vp and DP-Vp demonstrated good diagnostic performance among the qDCE parameters. Compared with the other TK models, the DP model has a higher AUC and a greater level of accuracy. The comprehensive model (AUC, 0.936, 0.884-0.988) demonstrated superiority in discriminating benign and malignant STTs, outperforming the qDCE models (AUC, 0.899-0.915) and the traditional imaging model (AUC, 0.802, 0.712-0.891) alone. CONCLUSIONS: Various TK models successfully distinguish benign from malignant STTs. The comprehensive model is a noninvasive approach incorporating morphological imaging aspects and qDCE parameters, and shows significant potential for further development.


Asunto(s)
Medios de Contraste , Imagen por Resonancia Magnética , Neoplasias de los Tejidos Blandos , Humanos , Persona de Mediana Edad , Masculino , Adulto , Anciano , Femenino , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Adolescente , Imagen por Resonancia Magnética/métodos , Anciano de 80 o más Años , Adulto Joven , Diagnóstico Diferencial , Cinética
5.
Biomed Pharmacother ; 176: 116754, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810401

RESUMEN

Alzheimer's disease (AD) presents a significant challenge due to its prevalence and lack of cure, driving the quest for effective treatments. Anshen Bunao Syrup, a traditional Chinese medicine known for its neuroprotective properties, shows promise in addressing this need. However, understanding its precise mechanisms in AD remains elusive. This study aimed to investigate Anshen Bunao Syrup's therapeutic potential in AD treatment using a scopolamine-induced AD rat model. Assessments included novel-object recognition and Morris water maze tasks to evaluate spatial learning and memory, alongside Nissl staining and ELISA analyses for neuronal damage and biomarker levels. Results demonstrated that Anshen Bunao Syrup effectively mitigated cognitive dysfunction by inhibiting amyloid-ß and phosphorylation Tau aggregation, thereby reducing neuronal damage. Metabolomics profiling of rats cortex revealed alterations in key metabolites implicated in tryptophan and fatty acid metabolism pathways, suggesting a role in the therapeutic effects of Anshen Bunao Syrup. Additionally, ELISA and correlation analyses indicated attenuation of oxidative stress and immune response through metabolic remodeling. In conclusion, this study provides compelling evidence for the neuroprotective effects of Anshen Bunao Syrup in AD models, shedding light on its potential as a therapeutic agent for AD prevention and treatment.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos , Fármacos Neuroprotectores , Estrés Oxidativo , Ratas Sprague-Dawley , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Masculino , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/metabolismo , Ratas , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Péptidos beta-Amiloides/metabolismo , Aprendizaje por Laberinto/efectos de los fármacos , Escopolamina , Proteínas tau/metabolismo , Prueba del Laberinto Acuático de Morris/efectos de los fármacos
6.
J Cancer Res Clin Oncol ; 150(4): 194, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619631

RESUMEN

PURPOSE: Kidney clear cell carcinoma (KIRC) has a poor prognosis, high morbidity and mortality rates, and high invasion and metastasis rate, and effective therapeutic targets are lacking. zDHHC3 has been implicated in various cancers, but its specific role in KIRC remains unclear. METHODS: In this study, we performed a pan-cancer analysis, bioinformatics analysis, and cell experiment to detect the role of zDHHC3 in KIRC. RESULTS: zDHHC3 was significantly down-regulated in KIRC, and that its high expression was associated with favorable patient outcomes. We identified 202 hub genes that were most relevant to high zDHHC3 expression and KIRC, and found that they were involved mainly in ion transport and renal cell carcinoma. Among these hub genes, SLC9A2 was identified as a downstream gene of zDHHC3. zDHHC3 suppression led to decreased expression and S-palmitoylation of SLC9A2, which further inhibited the apoptosis of Caki-2 cells. CONCLUSION: Our findings suggest that zDHHC3 plays an important role in KIRC, due partly to its regulation of SLC9A2 S-palmitoylation. The targeting of the zDHHC3-SLC9A2 axis may provide a new option for the clinical treatment of KIRC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Apoptosis , Carcinoma de Células Renales/genética , Riñón , Neoplasias Renales/genética , Lipoilación
7.
Histopathology ; 85(2): 295-309, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38660975

RESUMEN

AIMS: Immunotherapy has brought a new era to cancer treatment, yet we lack dependable predictors for its effectiveness. This study explores the predictive significance of intratumour stroma proportion (iTSP) for treatment success and prognosis in non-small cell lung cancer (NSCLC) patients undergoing treatment with immune check-point inhibitors (ICIs) together with chemotherapy. METHODS AND RESULTS: We retrospectively collected data from patients with unresectable stage IIIB-IV NSCLC who were treated with first-line ICIs and chemotherapy. Each patient received a confirmed pathological diagnosis, and the pathologist evaluated the iTSP on haematoxylin and eosin (H&E)-stained sections of diagnostic tissue slides. Among the 102 H&E-stained biopsy samples, 61 (59.8%) were categorised as stroma-L (less than 50% iTSP), while 41 (40.2%) were classified as stroma-H (more than 50% iTSP). We observed that the stroma-L group exhibited a significantly better objective response rate (ORR) (72.1 versus 51.2%, P = 0.031) and deeper response depth (DpR) (-50.49 ± 28.79% versus -35.83 ± 29.91%, P = 0.015) compared to the stroma-H group. Furthermore, the stroma-L group showed longer median progression-free survival (PFS) (9.6 versus 6.0 months, P = 0.011) and overall survival (OS) (24.0 versus 12.2 months, P = 0.001) compared to the stroma-H group. Multivariate Cox proportional hazards regression analysis indicated that iTSP was a highly significant prognostic factor for both PFS [hazard ratio (HR) = 1.713; P = 0.030] and OS (HR = 2.225; P = 0.003). CONCLUSION: Our findings indicate that a lower iTSP corresponds to improved clinical outcomes and greater DpR in individuals with stage IIIB-IV NSCLC treated with first-line ICIs and chemotherapy. The iTSP could potentially serve as a predictive biomarker for ICIs therapy response.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Femenino , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Masculino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Pronóstico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias , Anciano de 80 o más Años , Resultado del Tratamiento
8.
Phys Chem Chem Phys ; 26(13): 10202-10213, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38497211

RESUMEN

Designing an electrocatalyst with high efficiency and product selectivity is always crucial for an electrocatalytic CO2 reduction reaction (CO2RR). Inspired by the great progress of two-dimensional (2D) nanomaterials growing on Cu surfaces and their promising CO2RR catalytic efficiencies at their interfaces, the unique performance of Cu-based 2D materials as high-efficiency and low-cost CO2RR electrocatalysts has attracted extensive attention. Herein, based on density functional theory (DFT) calculations, we proposed a composite structure of graphitic carbon nitride (g-C3N4) fragments loaded on a Cu surface to explore the CO2RR catalytic property of the interface between g-C3N4 and the Cu surface. Three composite interfaces of C3N4/Cu(111), C3N4/Cu(110) and C3N4/Cu(100) have been studied by considering the reaction sites of vertex nitrogen atoms, edge nitrogen atoms and the nearby Cu atoms. It was found that the C3N4/Cu interfaces where nitrogen atoms contact the Cu substrate present competitive CO2RR activity. Among them, C3N4/Cu(111)-N3 exhibited a better activity for CH3OH production, with a low overpotential of 0.38 V. For HCOOH and CH4 production, C3N4/Cu(111)-Cu and C3N4/Cu(100)-N1 have overpotentials of 0.26 V and 0.44 V. The electronic analysis indicates the electron transfer from the Cu substrate to the g-C3N4 fragment and mainly accumulates on the nitrogen atoms of the interface. Such charge accumulation can activate the adsorbed CO bond of CO2 and lead to lower energetic barriers of CO2RR. DFT calculations indicate that the boundary nitrogen sites reduced the energy barrier of *CHO, which is crucial for CO2RR, compared with that of the pristine Cu surface. Our study explores a new Cu-based electrocatalyst and indicates that the C3N4/Cu interface can enhance the activities and selectivity of CO2RR and open a new strategy to design high-efficiency electrocatalysts for CO2RR.

9.
Carbohydr Polym ; 330: 121840, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38368116

RESUMEN

In this work, we developed a strategy to construct poly (butylene adipate-co-terephthalate) (PBAT) composite plastics with excellent mechanical properties, superior thermal stability and enhanced biodegradability by combining acetylated celluloses (ECs) mediated by electron beam irradiation (EBI), which works as a toughening agent. With findings, the EBI pretreatment assisted with acetylation was applied to develop ECs materials with a higher degree of acetylation than acetylation alone. The pretreated ECs with increased hydrophobicity tended to decrease the chance of self-aggregation and enhanced the interfacial compatibility and adhesion with PBAT in PBAT/ECs composite plastics. Thus, PBAT/ECs composite plastics exhibited a smoother and more uniform surface structure during preparation and offered higher tensile strength, water vapor transmission rate, water absorption rate, thermal stability and degradation rate, and lower elongation at a break during application. On top of that, the PBAT/ECs composite plastics were characterized by a series of methods containing Fourier transform infrared spectroscopy and X-ray diffraction, indicating that these properties are mainly caused by the acetylation of hydroxyl groups from cellulose and carboxyl groups of PBAT. The work is expected to expand the application scope of PBAT and cellulose and provide an attainable solution for a biodegradable substitute for traditional plastics.

10.
Adv Mater ; 36(1): e2307035, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37739409

RESUMEN

The development of nonprecious metal catalysts to meet the activity-stability balance at industrial-grade large current densities remains a challenge toward practical alkali-water electrolysis. Here, this work develops an orderly nanodendritic nickel (ND-Ni) catalyst that consists of ultrafine nanograins in chain-like conformation, which shows both excellent activity and robust stability for large current density hydrogen evolution reaction (HER) in alkaline media, superior to currently applied Raney nickel (R-Ni) catalyst in commercial alkali-water electrolyzer (AWE). The ND-Ni catalyst featured by a three-dimensional (3D) interconnecting microporous structure endows with high specific surface area and excellent conductivity and hydrophilicity, which together afford superior charge/mass transport favorable to HER kinetics at high current densities. An actual AWE with ND-Ni catalyst demonstrates durable water splitting with 1.0 A cm-2 at 1.71 V under industrial conditions and renders a record-low power consumption of 3.95 kW h Nm-3 with an energy efficiency close to 90%. The hydrogen price per gallon of gasoline equivalent (GGE) is calculated to be ≈$0.95, which is less than the target of $2.0 per GGE by 2026 from the U.S. Department of Energy. The results suggest the feasibility of ND-Ni substitute for R-Ni catalyst in commercial AWE.

11.
Biomed Pharmacother ; 170: 115679, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38113632

RESUMEN

Bacopaside I (BSI) is a natural compound that is difficult to absorb orally but has been shown to have antidepressant effects. The microbiota-gut-brain axis is involved in the development of depression through the peripheral nervous system, endocrine system, and immune system and may be a key factor in the effect of BSI. Therefore, this study aimed to investigate the potential mechanism of BSI in the treatment of depression via the microbiota-gut-brain axis and to validate it in a fecal microbiota transplantation model. The antidepressant effect of BSI was established in CUMS-induced mice using behavioral tests and measurement of changes in hypothalamicpituitaryadrenal (HPA) axis-related hormones. The improvement of stress-induced gut-brain axis damage by BSI was observed by histopathological sections and enzyme-linked immunosorbent assay (ELISA). 16 S rDNA sequencing analysis indicated that BSI could modulate the abundance of gut microbiota and increase the abundance of probiotic bacteria. We also observed an increase in short-chain fatty acids, particularly acetic acid. In addition, BSI could modulate the disruption of lipid metabolism induced by CUMS. Fecal microbiota transplantation further confirmed that disruption of the microbiota-gut-brain axis is closely associated with the development of depression, and that the microbiota regulated by BSI exerts a partial antidepressant effect. In conclusion, BSI exerts antidepressant effects by remodeling gut microbiota, specifically through the Lactobacillus and Streptococcus-acetic acid-neurotrophin signaling pathways. Furthermore, BSI can repair damage to the gut-brain axis, regulate HPA axis dysfunction, and maintain immune homeostasis.


Asunto(s)
Microbioma Gastrointestinal , Ratones , Animales , Depresión/metabolismo , Sistema Hipotálamo-Hipofisario , Sistema Hipófiso-Suprarrenal , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Acetatos/farmacología , Estrés Psicológico/metabolismo
12.
Inorg Chem ; 62(51): 21115-21127, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38063020

RESUMEN

Based on the density functional theory (DFT) calculations, we explored the structures and HER catalytic properties of reconstructed and double-stacked black phosphorene (BP) edges. Ten bilayer BP edges were constructed by the double stacking of three typical monolayer edges, i.e., zigzag (ZZ) edge, armchair (AC) edge, skewed diagonal (SD) edge, and their reconstructed derivatives with their layer's configurations, edge deformations and thermodynamic stabilities were discussed. Based on these edges, five chemical sites on four bilayer BP edges were selected to be promising candidates for a HER catalyst, which present higher HER activities than that of Pt(111). Besides, among these four edges, two edges have even lower energetic barriers for the Tafel reaction. Compared with the monolayer edges, these selected bilayer BP edges confirm the remarkable enhancement of the HER catalytic properties, which can be attributed to their unique edge structures and the enhanced electronic densities after the hydrogen adsorptions. Finally, the thermostability of these edges at room temperature has also been proved by the DFT-MD simulations. This theoretic study deepens our fundamental understanding of the double-stacked edge structures of the BP and provides a new way for the rational design of highly efficient and noble-metal-free HER catalysts.

13.
Molecules ; 28(24)2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38138435

RESUMEN

Currently, two-dimensional (2D) materials with intrinsic antiferromagnetism have stimulated research interest due to their insensitivity to external magnetic fields and absence of stray fields. Here, we predict a family of stable transition metal (TM) borides, TMB12 (TM = V, Cr, Mn, Fe) monolayers, by combining TM atoms and B12 icosahedra based on first-principles calculations. Our results show that the four TMB12 monolayers have stable antiferromagnetic (AFM) ground states with large magnetic anisotropic energy. Among them, three TMB12 (TM=V, Cr, Mn) monolayers display an in-plane easy magnetization axis, while the FeB12 monolayer has an out-of-plane easy magnetization axis. Among them, the CrB12 and the FeB12 monolayers are AFM semiconductors with band gaps of 0.13 eV and 0.35 eV, respectively. In particular, the AFM FeB12 monolayer is a spin-polarized AFM material with a Néel temperature of 125 K. Moreover, the electronic and magnetic properties of the CrB12 and the FeB12 monolayers can be modulated by imposing external biaxial strains. Our findings show that the TMB12 monolayers are candidates for designing 2D AFM materials, with potential applications in electronic devices.

14.
Nanoscale ; 15(46): 18745-18752, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37955150

RESUMEN

To realize the quantum anomalous Hall (QAH) effect in two-dimensional (2D) intrinsic magnetic materials, which combines insulating bulk states and metallic edge channel states, is still challenging in experiment. Here, based on first-principles calculations, we predicted two stable kagome-latticed QAH insulators: Cr3Se4 and Fe3S4 monolayers, with the Chern number C = 1. It is found that both structures exhibit a large magnetic anisotropy energy and sizable band gaps, and a topological phase transition from C = -1 to C = 1 occurs when the magnetization orientation changes from the z-axis to the -z-axis. Remarkably, the non-trivial topological properties are robust against biaxial strains of up to ±6%. Furthermore, a variable high Chern number of C = 2 or C = 3 can be observed by stacking two or three layers of the QAH monolayer with an MoS2 insulator. Our results signify that such layered kagome materials can be promising platforms for exploring novel QAH physics.

15.
J Phys Chem Lett ; 14(44): 9804-9810, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37889204

RESUMEN

Compared with single-atom catalysts, clusters not only possess more metal-loadings and stability but also provide flexible active sites to break the linear scaling relationship of multistep reactions. However, exploring precise structure-activity relationships and the synergistic effect between clusters and nanosheets is still in its infancy. Here, based on first-principles and nonequilibrium Green's function simulation, the C2N-supported Fe and Co tetrahedral clusters exhibit remarkable bifunctional catalytic performance with a very low overpotential of hydrogen (0.12 and 0.07 V) /oxygen (0.20 and 0.55 V) evolution reactions (HER/OER), respectively. The C2N-regulated Fe and Co clusters have suitable d-band centers around the Fermi surface for HER. In turn, the Fe and Co clusters activate the subadjacent dual-carbon sites for OER. Simultaneously, the cluster enhances the electronic conductivity of C2N, and the initial current only needs ultralow bias voltage around 0.1-0.4 V. The desired metal cluster regulation strategy offers cost-effective potential for advancing clean energy technology.

16.
J Phys Condens Matter ; 36(3)2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37774718

RESUMEN

We construct an islamic lattice by considering the nearest-neighbor (NN) hoppings with staggered magnetic fluxes and the next-NN hoppings. This model supports abundant quantum phases for various values of filling fractions. At1/4filling, Chern insulator (CI) phases with Chern numbersC=±1, -2and a zero-Chern-number topological insulator (ZCNTI) phase exist. At3/8filling, several CI phases with Chern numbersC=±1, 3and the ZCNTI phase are obtained. For the filling fraction 3/4, CI phases with Chern numbersC=±1, 2and two ZCNTI phase areas appear. Interestingly, these ZCNTI phases host both robust corner states and gapless edge states which can be characterized by the quantized polarization and quadrupole moment. We further find that staggered magnetic fluxes can give rise to the ZCNTI state at1/4and3/4fillings. Phase diagrams for filling fractions1/8,1/2,5/8and7/8are presented as well. In addition, flat bands are obtained for various filling fractions by tuning the hopping parameters. At 1/8 filling, a best topological flat band (TFB) with flatness ratio about 12 appears. Several trivial flat bands but with total Chern number|C|=1emerge in this model and exactly flat band is found at 3/8 filling. We further investigateν=1/2fractional Chern insulate state when hard-core bosons fill into this TFB model.

17.
Nat Prod Res ; : 1-4, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37712410

RESUMEN

Phytochemical investigation of EtOH extract of Pittosporum heterophyllum led to one new esterified thujane monoterpenoid glycoside, pitheteroside A (1), together with one eudesmane sesquiterpenoid (2) and twelve lignans (3-14). Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, ECD calculation and HRESIMS spectra. Pitheteroside A is an unreported and highly esterified monoterpenoid glycoside. All isolates were evaluated for their nitric oxide production inhibition against LPS-induced BV-2 microglial cells. Among them, compounds 1, 6 and 8 showed significant activities with IC50 values less than 10 µM. The results indicated the metabolisms from P. heterophyllum possess potential anti-inflammatory effects.

18.
Sci Rep ; 13(1): 14430, 2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37660085

RESUMEN

Gallate material, a luminescent matrix with excellent performance is normally prepared by vapor deposition or solid phase sintering method at high temperature. However, it has not been solved to prepare gallate-based fluorescent materials with full-color luminescent properties at low temperature. In this paper, ZnGa2O4 undoped or doped with Cr or Mn nanoflowers composed of nanosheet-level structure were prepared by hydrothermal method at low temperature. Under ultraviolet light irradiation, ZnGa2O4, ZnGa2O4:Mn2+ and ZnGa2O4:Cr3+ display three primary colors of blue, green and red luminescence through self-excitation, Mn2+ and Cr3+ excitation respectively. The solid fluorescence yields of blue, green, and red colors are 32.3, 36.5, and 40.7%, respectively. It is highly expected to be applied to color display, biological imaging, white light devices.

19.
Phytochemistry ; 215: 113833, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37625681

RESUMEN

Chemical investigation of the EtOAc extract of the leaves of Pittosporum lenticellatum led to the isolation of twenty-five previously undescribed eudesmane sesquiterpenoid glycosides, pitlencosides A-Y (1-25); their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, ECD spectra, and X-ray crystallographic analysis. Among them, compounds 4, 5, 7, 8, 15 and 16 exhibited significant inhibitory effects on the production of nitric oxide in lipopolysaccharide-induced BV-2 microglial cells by suppressing the expression of inducible nitric oxide synthase and cyclooxygenase-2, with IC50 values ranging from 7.95 to 25.88 µM, which showed stereo-chemical and substituent dependents. Western blot analysis and molecular docking simulation confirmed the anti-inflammatory activity of compounds 4, 5, 7, 8, 15 and 16.


Asunto(s)
Sesquiterpenos de Eudesmano , Sesquiterpenos , Estructura Molecular , Simulación del Acoplamiento Molecular , Sesquiterpenos de Eudesmano/farmacología , Sesquiterpenos de Eudesmano/química , Espectroscopía de Resonancia Magnética , Sesquiterpenos/química , Óxido Nítrico , Glicósidos/farmacología
20.
ACS Nano ; 17(16): 15568-15589, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37531599

RESUMEN

Due to the increasing antibiotic resistance and the lack of broad-spectrum antibiotics, there is an urgent requirement to develop fresh strategies to combat multidrug-resistant pathogens. Herein, defect-rich bismuth molybdate heterojunctions [zero-dimensional (0D) Bi4MoO9/two-dimensional (2D) Bi2MoO6, MBO] were designed for rapid capture of bacteria and synergistic photocatalytic sterilization. The as-prepared MBO was experimentally and theoretically demonstrated to possess defects, heterojunctions, and irradiation triple-enhanced photocatalytic activity for efficient generation of reactive oxygen species (ROS) due to the exposure of more active sites and separation of effective electron-hole pairs. Meanwhile, dopamine-modified MBO (pMBO) achieved a positively charged and rough surface, which conferred strong bacterial adhesion and physical penetration to the nanosheets, effectively trapping bacteria within the damage range and enhancing ROS damage. Based on this potent antibacterial ability of pMBO, a multifunctional hydrogel consisting of poly(vinyl alcohol) cross-linked tannic acid-coated cellulose nanocrystals (CPTB) and pMBO, namely CPTB@pMBO, is developed and convincingly effective against methicillin-resistant Staphylococcus aureus in a mouse skin infection model. In addition, the strategy of combining a failed beta-lactam antibiotic with CPTB@pMBO to photoinactivation with no resistance observed was developed, which presented an idea to address the issue of antibiotic resistance in bacteria and to explore facile anti-infection methods. In addition, CPTB@pMBO can reduce excessive proteolysis of tissue and inflammatory response by regulating the expression of genes and pro-inflammatory factors in vivo, holding great potential for the effective treatment of wound infections caused by drug-resistant bacteria.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Animales , Ratones , Bismuto/farmacología , Bismuto/química , Hidrogeles/farmacología , Especies Reactivas de Oxígeno/farmacología , Antibacterianos/farmacología , Antibacterianos/química
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