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1.
Braz J Otorhinolaryngol ; 90(6): 101473, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39111129

RESUMEN

OBJECTIVE: To investigate the efficacy of cluster nursing intervention based on Enhanced Recovery After Surgery (ERAS) for xerostomia in chronic rhinosinusitis after nasal endoscopic surgery. METHODS: A total of 80 patients with chronic rhinosinusitis who underwent functional nasal endoscopic surgery between January 2020 and December 2021 were selected and randomly divided into a control group (n = 40) and an experimental group (n = 40). Patients in the control group were treated with general nursing, while ERAS-based cluster nursing intervention was adopted for the experimental group, in addition to general nursing. Xerostomia stage and comfort level were observed at 2 h, 6 h, 24 h and 48 h after surgery; negative emotions before and after nursing were also observed. RESULTS: After the intervention, the xerostomia stage and comfort level at 6, 24 and 48 after surgery were higher in the experimental group (p < 0.05). Negative emotions in the experimental group were lower after nursing (p < 0.001). The self-rating depression scale and self-rating anxiety scale scores increased after nursing in both two groups (p < 0.05). CONCLUSION: Enhanced recovery after surgery-based cluster nursing intervention can alleviate xerostomia, improve patients' comfort levels, reduce their negative emotions and accelerate postoperative recovery.

2.
Int J Radiat Biol ; : 1-9, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136543

RESUMEN

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) is globally prevalent with high recurrence, low survival rate, and poor quality of life for patients. Derived from PAC-1, SM-1 can activate procaspase-3 and induce apoptosis in cancer cells to exert anti-tumor effects. However, the inhibitory effect of SM-1 on HNSCC after combination with radiation are unclear. This study aims to investigate the radiosensitizing effect of SM-1 on HNSCC in vitro and in vivo. METHODS: MTT method was used to detect the effect of SM-1 on the viability of HNSCC cell lines (HONE1, HSC-2, and CAL27). The effects of SM-1 combined with radiation on the survival index of HONE1, HSC-2, and CAL27 cell lines were determined by colony formation assay. Flow cytometry was used to investigate the effects of SM-1 and radiation combination on cell apoptosis and cell cycle, and western blot experiments were performed to detect the expression of apoptosis and cell cycle-related proteins. Finally, a xenograft tumor model of CAL27 was established to evaluate the anti-tumor effect of SM-1 combined with radiation in vivo. RESULTS: In vitro, SM-1 effectively inhibited the activity of HNSCC cell lines HONE1, HSC-2, and CAL27 cells, and synergistically showed anti-proliferation activity during combined irradiation. Meanwhile, anti-tumor effect of SM-1 on HNSCC was higher than that of Debio1143, and the radiosensitivity of cells was greatly increased. Flow cytometry and western blot analysis showed that SM-1 induced G2/M phase arrest of head and neck squamous cell carcinoma cells via inhibiting the expression of CyclinB1 and CDC2. Moreover, SM-1 activated caspase-3 activity and up-regulated the cleaved form of PARP1 to induce cell apoptosis. In vivo, SM-1 combined irradiation showed a good anti-tumor effect. CONCLUSION: SM-1 enhances HNSCC cell radiation sensitivity in vitro and in vivo, supporting its potential as a radiosensitizer for clinical trials in combination with radiotherapy.

3.
Mater Horiz ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39145397

RESUMEN

Skyrmion-bimeron switching is one of the most important phenomena in topological magnetism. Currently, it is usually realized by the annoying spin orientation vertical-reversal through magnetic field. Based on first-principles calculations and atomic spin simulations, we alternatively unveil that the switching between magnetic skyrmions and bimerons can be achieved in topological magnetic monolayer CrSeBr by external strain. The core mechanism of this switching is traced to the controllable magnetic anisotropy of monolayer CrSeBr influenced by the strain-engineered low-energy states around the Fermi level. We also introduce a parameter |κ| as a criterion for judging the stability of magnetic skyrmions and bimerons, which can be adopted as a useful descriptor linking the presence of skyrmion-bimeron switching driven by strain. The underlying physics is discussed in detail. The predicted strain controlled skyrmion-bimeron switching may be interesting for topological magnetic devices.

4.
Nano Lett ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150250

RESUMEN

Engineering the valley index is essential and highly sought for valley physics, but currently, it is exclusively based on the paradigm of the challenging ferrovalley with spin-orientation reversal under a magnetic field. Here, an alternative strategy, i.e., the so-called ferroelectrovalley, is proposed to tackle the insurmountable spin-orientation reversal, which reverses the valley index with the feasible ferroelectricity. Using symmetry arguments and the tight-binding model, the C2z rotation is unveiled to be able to take the place of time reversal for operating the valley index in two-dimensional multiferroic kagome lattices, which enables a ferroelectricity-engineered valley index, thereby generating the concept of a ferroelectrovalley. Based on first-principles calculations, this concept is further demonstrated in the breathing kagome lattice of single-layer Ti3Br8, wherein ferroelectricity couples with the breathing process. These findings open a new direction for valleytronics and 2D materials research.

5.
Front Pharmacol ; 15: 1309540, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948470

RESUMEN

Background: Few studies have analysed oxaliplatin-induced adverse events (ADEs) in the immune system and skin and subcutaneous tissues through pharmacovigilance. We used this approach to analyse the risk of such ADEs when oxaliplatin combined with immune checkpoint inhibitors (ICIs). Methods: We evaluated the association between oxaliplatin and ADEs in the immune system and skin and subcutaneous tissues using the reporting odd ratio (ROR) for mining the ADE report signals in the FDA Adverse Event Reporting System database. Risk factors were analyzed using a binary logistic regression analysis using the sex and age of the patients. Results: There were 40,474 reports of oxaliplatin as primary suspect drug or second suspect drug. The signal intensities of ADEs such as type II hypersensitivity, type I hypersensitivity, type III immune complex-mediated reaction, anaphylactoid shock and cytokine release syndrome were high in PTs classified by SOC as immune system disorders; in the PTs classified as skin and subcutaneous tissue disorders by SOC, the signal intensities of ADEs such as skin toxicity, skin reaction, rash maculo-papular and skin fissures were higher. In the risk assessment between the two groups, rash showed an increased risk in the oxaliplatin-ICI group, with an OR of 1.96. Nivolumab in combination with oxaliplatin had an OR of 2.196 and an adjusted OR of 2.231. Combined with pembrolizumab, OR was 2.762 and the adjusted OR was 2.678. Conclusion: Type II hypersensitivity shows a stronger pharmacovigilance signal. Oxaliplatin in combination with nivolumab or pembrolizumab has been shown to increase the risk of rash.

6.
ACS Appl Mater Interfaces ; 16(29): 38466-38477, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38995996

RESUMEN

Prolonged sitting can easily result in pressure injury (PI) for certain people who have had strokes or spinal cord injuries. There are not many methods available for tracking contact surface pressure and shear force to evaluate the PI risk. Here, we propose a smart cushion that uses two-dimensional force sensors (2D-FSs) to measure the pressure and shear force in the buttocks. A machine learning algorithm is then used to compute the shear stresses in the gluteal muscles, which helps to determine the PI risk. The 2D-FS consists of a ferroelectret coaxial sensor (FCS) unit placed atop a ferroelectret film sensor (FFS) unit, allowing it to detect both vertical and horizontal forces simultaneously. To characterize and calibrate, two experimental approaches are applied: one involves simultaneously applying two perpendicular forces, and one involves applying a single force. To separate the two forces, the 2D-FS is decoupled using a deep neural network technique. Multiple FCSs are embedded to form a smart cushion, and a genetic algorithm-optimized backpropagation neural network is proposed and trained to predict the shear strain in the buttocks to prevent PI. By tracking the danger of PI, the smart cushion based on 2D-FSs may be further connected with home-based intelligent care platforms to increase patient equality for spinal cord injury patients and lower the expense of nursing or rehabilitation care.


Asunto(s)
Aprendizaje Automático , Úlcera por Presión , Úlcera por Presión/prevención & control , Humanos , Nalgas , Medición de Riesgo , Presión , Redes Neurales de la Computación , Algoritmos
7.
Angew Chem Int Ed Engl ; : e202410596, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031951

RESUMEN

Selective CO2 photoreduction to value-added multi-carbon (C2+) feedstocks, such as C2H4, holds great promise in direct solar-to-chemical conversion for a carbon-neutral future. Nevertheless, the performance is largely inhibited by the high energy barrier of C-C coupling process, thereby leading to C2+ products with low selectivity. Here we report that through facile surface immobilization of a 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF4) ionic liquid, plasmonic Cu nanowires could enable highly selective CO2 photoreduction to C2H4 product. At an optimal condition, the resultant plasmonic photocatalyst exhibits C2H4 production with selectivity up to 96.7% under 450 nm monochromatic light irradiation, greatly surpassing its pristine Cu counterpart. Combined in situ spectroscopies and computational calculations unravel that the addition of EMIM-BF4 ionic liquid modulates the local electronic structure of Cu, resulting in its enhanced adsorption strength of *CO intermediate and significantly reduced energy barrier of C-C coupling process. This work paves new path for Cu surface plasmons in selective artificial photosynthesis to targeted products.

8.
J Mol Model ; 30(8): 259, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977581

RESUMEN

CONTEXT: This study explores the impact of deformation on the electrical and optical characteristics of monolayer cadmium telluride (MoTe2) with vacancies, using the foundational principles of density functional theory. It was discovered that both strain and imperfections alter the electrical characteristics of monolayer MoTe2. Under VTe-MoTe2, a direct-to-indirect band-gap transition occurs. In DTe-MoTe2, the band-gap value reduces dramatically, the conduction band changes downward, and the carrier concentration rises. The DVTe-induced band gap state is closer to the Fermi energy level than the VTe-induced band gap state. In this paper, DTe-MoTe2 is chosen for tensile deformation. The results show that the band-gap value tends to decrease by increasing tensile deformation. When the stretching value reaches 10%, the lower bound of the conduction band and the top of the valence band overlap, and the system is converted from a semiconductor to a metal. Considering the density of states, the missing state MoTe2 is mainly contributed by the participation of Te-s, Te-p, and Mo-d orbitals. In terms of optical qualities, the absorption and reflection peaks are red-shifted and blue-shifted, respectively. It is hoped that these effects on the optoelectronic properties will be widely applied. METHODS: In this study, we utilize the generalized gradient approximation plane-wave pseudopotential method, incorporating Perdew-Burke Ernzerhof (PBE) generalized functions and following the fundamental principles of the density functional theory framework. A 3 × 3 × 1 supercell was constructed as an undoped model based on a MoTe2 monolayer, which consists of 9 Mo atoms and 18 Te atoms. The vacuum flat plate was set to 15 Å along the z-direction to avoid interactions between the monolayers. For electronic structure calculations, the energy cutoff was set to 450 eV. Each model's computational process and structural optimization were carried out using the Monkhorst-Pack specialized K-point sampling approach. Crystal optimization computations used a 3 × 3 × 1 Monkhorst-Pack K-point grid for molybdenum ditelluride monolayers and a 9 × 9 × 1 K-point grid for electronic system analysis, analyzing state density and optical characteristics, respectively. For the structural optimization, the convergence requirements for maximum force, maximum atom displacement, maximum stress, and energy change were defined at 0.03 eV/Å, 0.001 Å, 0.05 Gpa, and 1.0 × 10-5 eV/atom, respectively.

10.
BMC Psychiatry ; 24(1): 514, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030516

RESUMEN

BACKGROUND: In this prospective cohort study, we determined the phenotypic characteristics of children with regressive autism spectrum disorder (ASD) and explored the effects of rehabilitation. METHODS: We recruited 370 children with ASD aged 1.5-7 years. Based on the Regression Supplement Form, the children were assigned to two groups: regressive and non-regressive. The core symptoms and neurodevelopmental levels of ASD were assessed before and after 1 year of behavioral intervention using the Autism Diagnostic Observation Schedule (ADOS), Social Response Scale (SRS), Children Autism Rating Scale (CARS), and Gesell Developmental Scale (GDS). RESULTS: Among the 370 children with ASD, 28.38% (105/370) experienced regression. Regression was primarily observed in social communication and language skills. Children with regressive ASD exhibited higher SRS and CARS scores and lower GDS scores than those with non-regressive ASD. After 1 year of behavioral intervention, the symptom scale scores significantly decreased for all children with ASD; however, a lesser degree of improvement was observed in children with regressive ASD than in those with non-regressive ASD. In addition, the symptom scores of children with regressive ASD below 4 years old significantly decreased, whereas the scores of those over 4 years old did not significantly improve. Children with regressive ASD showed higher core symptom scores and lower neurodevelopmental levels. Nevertheless, after behavioral intervention, some symptoms exhibited significant improvements in children with regressive ASD under 4 years of age. CONCLUSION: Early intervention should be considered for children with ASD, particularly for those with regressive ASD.


Asunto(s)
Trastorno del Espectro Autista , Fenotipo , Humanos , Trastorno del Espectro Autista/rehabilitación , Trastorno del Espectro Autista/complicaciones , Preescolar , Masculino , Femenino , Niño , Estudios Prospectivos , Lactante , Terapia Conductista/métodos
11.
Int J Biol Macromol ; 275(Pt 2): 133669, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38971289

RESUMEN

Surface browning of plant-derived fresh-cut products is mainly caused by conversion of the phenolic compounds into o-quinones under tyrosinase catalysis. In this study, the rarely reported complex tannins from Euryale ferox seed shell (ECTs) constituted by the units of 35.60% condensed tannins and 64.40% hydrolysable tannins were shown to suppress the activity of tyrosinase efficiently, supporting the exploitation of ECTs into novel anti-browning agents. However, the utilization of ECTs in food preservation is often restricted because of their chemical instability to external environment. Further fabrication of nanoliposomes loaded with ECTs (ECTs-NLs) herein was carried out to improve the stability of ECTs. DLS, TEM, FTIR, DSC and XRD confirmed that ECTs were encapsulated into nanoliposomes successfully, and ECTs-NLs appeared as vesicle-like spherical morphology with favorable encapsulation efficiency, uniform particle size distribution and negative zeta-potential. The resulting ECTs-NLs were relatively stable in the dark at 4 °C. Nanoliposomal encapsulation significantly enhanced ECTs stability, thus protecting inhibitory effect of ECTs against tyrosinase. Furthermore, anti-browning evaluation proved that ECTs-NLs had distinct advantages over free ECTs in alleviating surface browning of fresh-cut asparagus lettuces. These results suggested that nanoliposomes were effective in stabilizing ECTs and ECTs-NLs could be potentially applied to the fresh-cut food industry.


Asunto(s)
Asparagus , Liposomas , Monofenol Monooxigenasa , Semillas , Taninos , Liposomas/química , Semillas/química , Asparagus/química , Taninos/química , Monofenol Monooxigenasa/antagonistas & inhibidores , Nanopartículas/química , Tamaño de la Partícula , Nymphaeaceae/química
12.
Chemistry ; : e202401380, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987889

RESUMEN

Photocatalytic ozonation is considered to be a promising approach for the treatment of refractory organic pollutants, but the design of efficient catalyst remains a challenge. Surface modification provides a potential strategy to improve the activity of photocatalytic ozonation. In this work, density functional theory (DFT) calculations were first performed to check the interaction between O3 and TiO2-OH (surface hydroxylated TiO2) or TiO2-F (surface fluorinated TiO2), and the results suggest that TiO2-OH displays better O3 adsorption and activation than does TiO2-F, which is confirmed by experimental results. The surface hydroxyl groups greatly promote the O3 activation, which is beneficial for the generation of reactive oxygen species (ROS). Importantly, TiO2-OH displays better performance towards pollutants (such as berberine hydrochloride) removal than does TiO2-F and most reported ozonation photocatalysts. The total organic carbon (TOC) removal efficiency reaches 84.4 % within two hours. This work highlights the effect of surface hydroxylation on photocatalytic ozonation and provides ideas for the design of efficient photocatalytic ozonation catalysts.

13.
J Phys Chem Lett ; 15(26): 6699-6704, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38900495

RESUMEN

Coupling the spin Hall effect with novel degrees of freedom of electrons is central to the rich phenomena observed in condensed-matter physics. Here, using symmetry analysis and a low-energy k·p model, we report the sliding ferroelectricity engineered coupling between spin Hall effect and emerging layertronics, thereby generating the layer spin Hall effect (LSHE), in a 2D lattice. The physics is rooted in a pair of T-symmetry connected valleys, which experience spin splitting accompanied by large Berry curvature under spin-orbit coupling. The interaction between the out-of-plane ferroelectricity and electronic properties gives rise to the layer-locked Berry curvature and thus layer-polarized spin Hall effect (LP-SHE) in the bilayers. Such LP-SHE is strongly coupled with sliding ferroelectricity, enabling it to be ferroelectrically reversible. Using first-principles calculations, the mechanism is further demonstrated in a series of real bilayer systems, including MoS2, MoTe2, WSe2, MoSi2P4, and MoSi2As4. These phenomena and insights open a new direction for spin Hall effect.

14.
J Hazard Mater ; 474: 134840, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38865923

RESUMEN

Electrochemical advanced oxidation processes (EAOP) have shown great potential for the abatement of complexed heavy metals, such as metal-EDTA complexes, in recent studies. While removal of metal-EDTA complexes has been extensively examined in bench-scale reactors, much less attention has been given to the efficacy of this process at larger scale. In this study, we utilize a 72 L pilot-scale continuous flow system comprised of six serpentine flow channels and 90 pairs of flow-through electrodes for the degradation of Ni-EDTA complexes and removal of Ni from solution. The influence of a range of key operating parameters including flow rate, current density and initial Ni-EDTA concentration on rate and extent of Ni-EDTA degradation and Ni removal were examined. Our results showed that at a feed flow rate of 36 L h-1, current density of 5 mA cm-2 and initial Ni-EDTA concentration of 1 mM, the pilot-scale system achieved 74 % total Ni removal, 78 % total EDTA removal and 40 % TOC removal with energy consumption of 13.6 kWh m-3 order-1 and energy efficiency of 7.9 g kWh-1 for total Ni removal. A mechanistically-based kinetic model, which was developed in our previous bench-scale study, provides a satisfactory description of the experimental results obtained in the pilot-scale unit. Long term operation of the pilot-scale unit resulted in corrosion of PbO2 anode along with inorganic scaling as well as organic fouling on the PbO2 surface resulting in an obvious decline in Ni-EDTA degradation. Overall, the results of this study suggest that large scale anodic oxidation of wastewaters containing metal-organic complexes is an effective means of degrading organic ligands thereby enabling removal of the metal at the cathode. However, additional efforts are required to enhance the durability of the anode material and reduce material costs and energy consumption.

15.
Food Funct ; 15(13): 6798-6824, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38836693

RESUMEN

In recent decades, natural compounds derived from herbal medicine or dietary sources have played important roles in prevention and treatment of various diseases and have attracted more and more attention. Curcumin, extracted from the Curcumae Longae Rhizoma and widely used as food spice and coloring agent, has been proven to possess high pharmacological value. However, the pharmacological application of curcumin is limited due to its poor systemic bioavailability. As a major active metabolite of curcumin, tetrahydrocurcumin (THC) has higher bioavailability and stability than curcumin. Increasing evidence confirmed that THC had a wide range of biological activities and significant treatment effects on diseases. In this paper, we reviewed the research progress on the biological activities and therapeutic potential of THC on different diseases such as neurological disorders, metabolic syndromes, cancers, and inflammatory diseases. The extensive pharmacological effects of THC involve the modulation of various signaling transduction pathways including MAPK, JAK/STAT, NF-κB, Nrf2, PI3K/Akt/mTOR, AMPK, Wnt/ß-catenin. In addition, the pharmacokinetics, drug combination and toxicology of THC were discussed, thus providing scientific basis for the safe application of THC and the development of its dietary supplements and drugs.


Asunto(s)
Curcumina , Curcumina/farmacología , Curcumina/análogos & derivados , Curcumina/química , Humanos , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/prevención & control , Neoplasias/metabolismo , Transducción de Señal/efectos de los fármacos , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Enfermedades del Sistema Nervioso/prevención & control , Curcuma/química , Inflamación/tratamiento farmacológico , Inflamación/prevención & control , Enfermedades Metabólicas/prevención & control , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/metabolismo
16.
Front Neurosci ; 18: 1368552, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716255

RESUMEN

Probucol has been utilized as a cholesterol-lowering drug with antioxidative properties. However, the impact and fundamental mechanisms of probucol in obesity-related cognitive decline are unclear. In this study, male C57BL/6J mice were allocated to a normal chow diet (NCD) group or a high-fat diet (HFD) group, followed by administration of probucol to half of the mice on the HFD regimen. Subsequently, the mice were subjected to a series of behavioral assessments, alongside the measurement of metabolic and redox parameters. Notably, probucol treatment effectively alleviates cognitive and social impairments induced by HFD in mice, while exhibiting no discernible influence on mood-related behaviors. Notably, the beneficial effects of probucol arise independently of rectifying obesity or restoring systemic glucose and lipid homeostasis, as evidenced by the lack of changes in body weight, serum cholesterol levels, blood glucose, hyperinsulinemia, systemic insulin resistance, and oxidative stress. Instead, probucol could regulate the levels of nitric oxide and superoxide-generating proteins, and it could specifically alleviate HFD-induced hippocampal insulin resistance. These findings shed light on the potential role of probucol in modulating obesity-related cognitive decline and urge reevaluation of the underlying mechanisms by which probucol exerts its beneficial effects.

17.
Cell Stem Cell ; 31(7): 961-973.e8, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38759653

RESUMEN

ß0/ß0 thalassemia is the most severe type of transfusion-dependent ß-thalassemia (TDT) and is still a challenge facing lentiviral gene therapy. Here, we report the interim analysis of a single-center, single-arm pilot trial (NCT05015920) evaluating the safety and efficacy of a ß-globin expression-optimized and insulator-engineered lentivirus-modified cell product (BD211) in ß0/ß0 TDT. Two female children were enrolled, infused with BD211, and followed up for an average of 25.5 months. Engraftment of genetically modified hematopoietic stem and progenitor cells was successful and sustained in both patients. No unexpected safety issues occurred during conditioning or after infusion. Both patients achieved transfusion independence for over 22 months. The treatment extended the lifespan of red blood cells by over 42 days. Single-cell DNA/RNA-sequencing analysis of the dynamic changes of gene-modified cells, transgene expression, and oncogene activation showed no notable adverse effects. Optimized lentiviral gene therapy may safely and effectively treat all ß-thalassemia.


Asunto(s)
Terapia Genética , Lentivirus , Globinas beta , Talasemia beta , Humanos , Talasemia beta/terapia , Talasemia beta/genética , Proyectos Piloto , Femenino , Lentivirus/genética , Globinas beta/genética , Niño , Transfusión Sanguínea , Preescolar
18.
ACS Nano ; 18(20): 13377-13383, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38728267

RESUMEN

Magnetic materials offer a fertile playground for fundamental physics discovery, with not only electronic but also magnonic topological states intensively explored. However, one natural material with both electronic and magnonic nontrivial topologies is still unknown. Here, we demonstrate the coexistence of first-order topological magnon insulators (TMIs) and electronic second-order topological insulators (SOTIs) in 2D honeycomb ferromagnets, giving rise to the nontrivial corner states being connected by the charge-free magnonic edge states. We show that, with C3 symmetry, the phase factor ± ϕ caused by the next nearest-neighbor Dzyaloshinskii-Moriya interaction breaks the pseudo-spin time-reversal symmetry T, which leads to the split of magnon bands, i.e., the emergence of TMIs with a nonzero Chern number of C=-1, in experimentally feasible candidates of MoI3, CrSiTe3, and CrGeTe3 monolayers. Moreover, protected by the C3 symmetry, the electronic SOTIs characterized by nontrivial corner states are obtained, bridging the topological aspect of fermions and bosons with a high possibility of innovative applications in spintronics devices.

19.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2376-2384, 2024 May.
Artículo en Chino | MEDLINE | ID: mdl-38812138

RESUMEN

The abnormal activation of the mammalian target of rapamycin(mTOR) signaling pathway in non-small cell lung cancer(NSCLC) is closely associated with distant metastasis, drug resistance, tumor immune escape, and low overall survival. The present study reported that betulinic acid(BA), a potent inhibitor of mTOR signaling pathway, exhibited an inhibitory activity against NSCLC in vitro and in vivo. CCK-8 and colony formation results demonstrated that BA significantly inhibited the viability and clonogenic ability of H1299, A549, and LLC cells. Additionally, the treatment with BA induced mitochondrion-mediated apoptosis of H1299 and LLC cells. Furthermore, BA inhibited the mobility and invasion of H1299 and LLC cells by down-regulating the expression level of matrix metalloproteinase 2(MMP2) and impairing epithelial-mesenchymal transition. The results demonstrated that the inhibition of mTOR signaling pathway by BA decreased the proportion of M2 phenotype(CD206 positive) cells in total macrophages. Furthermore, a mouse model of subcutaneous tumor was established with LLC cells to evaluate the anti-tumor efficiency of BA in vivo. The results revealed that the administration of BA dramatically retarded the tumor growth and inhibited the proliferation of tumor cells. More importantly, BA increased the ratio of M1/M2 macrophages in the tumor tissue, which implied the enhancement of anti-tumor immunity. In conclusion, BA demonstrated the inhibitory effect on NSCLC by repolarizing tumor-associated macrophages via the mTOR signaling pathway.


Asunto(s)
Ácido Betulínico , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Triterpenos Pentacíclicos , Transducción de Señal , Serina-Treonina Quinasas TOR , Macrófagos Asociados a Tumores , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/genética , Animales , Ratones , Transducción de Señal/efectos de los fármacos , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Triterpenos Pentacíclicos/farmacología , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología , Línea Celular Tumoral , Triterpenos/farmacología , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos
20.
Mater Horiz ; 11(16): 3819-3824, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38805308

RESUMEN

We show that circularly polarized light is a versatile way to manipulate both the orbital Hall effect and band topology in two-dimensional ferromagnets. Employing the hexagonal lattice, we proposed that interactions between light and matter allow for the modulation of the valley polarization effect, and then band inversions, accompanied by the band gap closing and reopening processes, can be achieved subsequently at two valleys. Remarkably, the distribution of orbital angular momentum can be controlled by the band inversions, leading to the Floquet engineering of the orbital Hall effect, as well as the topological phase transition from a second-order topological insulator to a Chern insulator with in-plane magnetization, and then to a normal insulator. Furthermore, first-principles calculations validate the feasibility with the 2H-ScI2 monolayer as a candidate material, paving a technological avenue to bridge the orbitronics and nontrivial topology using Floquet engineering.

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