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1.
Nano Lett ; 24(30): 9186-9194, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39012034

RESUMO

The interaction between light and moiré superlattices presents a platform for exploring unique light-matter phenomena. Tailoring these optical properties holds immense potential for advancing the utilization of moiré superlattices in photonics, optoelectronics, and valleytronics. However, the control of the optical polarization state in moiré superlattices, particularly in the presence of moiré effects, remains elusive. Here, we unveil the emergence of optical anisotropy in moiré superlattices by constructing twisted WSe2/WSe2/SiP heterostructures. We report a linear polarization degree of ∼70% for moiré excitons, attributed to the spatially nonuniform charge distribution, corroborated by first-principles calculations. Furthermore, we demonstrate the modulation of this linear polarization state via the application of a magnetic field, resulting in polarization angle rotation and a magnetic-field-dependent linear polarization degree, influenced by valley coherence and moiré potential effects. Our findings demonstrate an efficient strategy for tuning the optical polarization state of moiré superlattices using heterointerface engineering.

2.
Nano Lett ; 24(26): 8189-8197, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38904278

RESUMO

IV-V two-dimensional materials have emerged as key contenders for polarization-sensitive and angle-resolved devices, given their inherent anisotropic physical properties. While these materials exhibit intriguing high-pressure quasi-particle behavior and phase transition, the evolution of quasi-particles and their interactions under external pressure remain elusive. Here, employing a diamond anvil cell and spectroscopic measurements coupled with first-principles calculations, we unveil rarely observed pressure-induced phonon-phonon coupling in layered SiP flakes. This coupling manifests as an anomalous phonon hardening behavior for the A1 mode within a broad wavenumber phonon softening region. Furthermore, we demonstrate the effective tuning of exciton emissions in SiP flakes under pressure, revealing a remarkable 63% enhancement in the degree of polarization (DOP) within the pressure range of 0-3.5 GPa. These findings contribute to our understanding of high-pressure phonon evolution in SiP materials and offer a strategic approach to manipulate the anisotropic performance of in-plane anisotropic 2D materials.

3.
J Am Chem Soc ; 146(6): 3890-3899, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38294957

RESUMO

Topological insulators offer significant potential to revolutionize diverse fields driven by nontrivial manifestations of their topological electronic band structures. However, the realization of superior integration between exotic topological states and superconductivity for practical applications remains a challenge, necessitating a profound understanding of intricate mechanisms. Here, we report experimental observations for a novel superconducting phase in the pressurized second-order topological insulator candidate Ta2Pd3Te5, and the high-pressure phase maintains its original ambient pressure lattice symmetry up to 45 GPa. Our in situ high-pressure synchrotron X-ray diffraction, electrical transport, infrared reflectance, and Raman spectroscopy measurements, in combination with rigorous theoretical calculations, provide compelling evidence for the association between the superconducting behavior and the densified phase. The electronic state change around 20 GPa was found to modify the topology of the Fermi surface directly, which synergistically fosters the emergence of robust superconductivity. In-depth comprehension of the fascinating properties exhibited by the compressed Ta2Pd3Te5 phase is achieved, highlighting the extraordinary potential of topological insulators for exploring and investigating high-performance electronic advanced devices under extreme conditions.

4.
Small ; : e2404346, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235385

RESUMO

Magnetic 2D materials offer a promising platform for manipulating quantum states at the nanoscale. Recent studies have underscored the significant influence of 2D magnetic materials on the optical behaviors of transition-metal dichalcogenides (TMDs), revealing phenomena such as interlayer exciton-magnon interactions, magnetization-dependent valley polarization, and an enhanced Zeeman effect. However, the controlled manipulation of anisotropic optical properties in TMDs via magnetism remains challenging. Here, the magnetic ordering in FePS3 profoundly impacts the optical characteristics of WSe2, achieving a giant linear polarization degree of 5.1 in exciton emission is demonstrated. This is supported by a detailed analysis of low-temperature photoluminescence (PL) and Raman spectra from nL-FePS3/WSe2 heterostructures. These findings indicate that a phase transition in FePS3 from paramagnetic to antiferromagnetic enhances interlayer Coulomb interactions, inducing a transition from non-polar to polar behavior in the heterostructures. Additionally, valley-polarized PL spectra under magnetic fields from -9 to 9 T reveal the influence of FePS3 on valley polarization and Zeeman splitting of excitons in monolayer WSe2. These results present a novel strategy for tailoring the optoelectronic properties of 2D magnetic van der Waals heterostructures, paving the way for advancements in nanoscale device design.

5.
FASEB J ; 37(1): e22699, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36520055

RESUMO

Cardiac fibrosis is an essential pathological process in pressure overload (PO)-induced heart failure. Recently, myocyte-fibroblast communication is proven to be critical in heart failure, in which, pathological growth of cardiomyocytes (CMs) may promote fibrosis via miRNAs-containing exosomes (Exos). Peli1 regulates the activation of NF-κB and AP-1, which has been demonstrated to engage in miRNA transcription in cardiomyocytes. Therefore, we hypothesized that Peli1 in CMs regulates the activation of cardiac fibroblasts (CFs) through an exosomal miRNA-mediated paracrine mechanism, thereby promoting cardiac fibrosis. We found that CM-conditional deletion of Peli1 improved PO-induced cardiac fibrosis. Moreover, Exos from mechanical stretch (MS)-induced WT CMs (WT MS-Exos) promote activation of CFs, Peli1-/- MS-Exos reversed it. Furthermore, miRNA microarray and qPCR analysis showed that miR-494-3p was increased in WT MS-Exos while being down regulated in Peli1-/- MS-Exos. Mechanistically, Peli1 promoted miR-494-3p expression via NF-κB/AP-1 in CMs, and then miR-494-3p induced CFs activation by inhibiting PTEN and amplifying the phosphorylation of AKT, SMAD2/3, and ERK. Collectively, our study suggests that CMs Peli1 contributes to myocardial fibrosis via CMs-derived miR-494-3p-enriched exosomes under PO, and provides a potential exosomal miRNA-based therapy for cardiac fibrosis.


Assuntos
Comunicação Celular , Exossomos , Insuficiência Cardíaca , Miócitos Cardíacos , Humanos , Exossomos/genética , Exossomos/metabolismo , Fibrose/etiologia , Fibrose/genética , Fibrose/metabolismo , Fibrose/patologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fator de Transcrição AP-1/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Cardiopatias/etiologia , Cardiopatias/genética , Cardiopatias/metabolismo , Cardiopatias/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Comunicação Celular/genética , Comunicação Celular/fisiologia
6.
Purinergic Signal ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489005

RESUMO

Berberine (BBR) is a Chinese herb with antioxidant and anti-inflammatory properties. In a previous study, we found that BBR had a protective effect against light-induced retinal degeneration in BALB/c mice. The purinergic P2X7 receptor (P2X7R) plays a key role in retinal degeneration via inducing oxidative stress, inflammatory changes, and cell death. The aim of this study was to investigate whether BBR can induce protective effects in light damage experiments and whether P2X7R can get involved in these effects. C57BL/6 J mice and P2X7 knockout (KO) mice on the C57BL/6 J background were used. We found that BBR preserved the outer nuclear layer (ONL) thickness and retinal ganglion cells following light stimulation. Furthermore, BBR significantly suppressed photoreceptor apoptosis, pro-apoptotic c-fos expression, pro-inflammatory responses of Mϋller cells, and inflammatory factors (TNF-α, IL-1ß). In addition, protein levels of P2X7R were downregulated in BBR-treated mice. Double immunofluorescence showed that BBR reduced overexpression of P2X7R in retinal ganglion cells and Mϋller cells. Furthermore, BBR combined with the P2X7R agonist BzATP blocked the effects of BBR on retinal morphology and photoreceptor apoptosis. However, in P2X7 KO mice, BBR had an additive effect resulting in thicker ONL and more photoreceptors. The data suggest that the P2X7 receptor is involved in retinal light damage, and BBR inhibits this process by reducing histological impairment, cell death, and inflammatory responses.

7.
Bioorg Chem ; 148: 107467, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772290

RESUMO

KRAS-G12C inhibitors has been made significant progress in the treatment of KRAS-G12C mutant cancers, but their clinical application is limited due to the adaptive resistance, motivating development of novel structural inhibitors. Herein, series of coumarin derivatives as KRAS-G12C inhibitors were found through virtual screening and rational structural optimization. Especially, K45 exhibited strong antiproliferative potency on NCI-H23 and NCI-H358 cancer cells harboring KRAS-G12C with the IC50 values of 0.77 µM and 1.50 µM, which was 15 and 11 times as potent as positive drug ARS1620, respectively. Furthermore, K45 reduced the phosphorylation of KRAS downstream effectors ERK and AKT by reducing the active form of KRAS (KRAS GTP) in NCI-H23 cells. In addition, K45 induced cell apoptosis by increasing the expression of anti-apoptotic protein BAD and BAX in NCI-H23 cells. Docking studies displayed that the 3-naphthylmethoxy moiety of K45 extended into the cryptic pocket formed by the residues Gln99 and Val9, which enhanced the interaction with the KRAS-G12C protein. These results indicated that K45 was a potent KRAS-G12C inhibitor worthy of further study.


Assuntos
Antineoplásicos , Proliferação de Células , Cumarínicos , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Cumarínicos/química , Cumarínicos/farmacologia , Cumarínicos/síntese química , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Descoberta de Drogas , Apoptose/efeitos dos fármacos , Simulação de Acoplamento Molecular , Avaliação Pré-Clínica de Medicamentos
8.
Arch Gynecol Obstet ; 309(1): 249-258, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37493777

RESUMO

PURPOSE: This study aimed to evaluate the effects of a one-session sexual health education program using a transtheoretical model to enhance sexual self-efficacy in patients with cervical cancer. METHODS: This study recruited patients with cervical cancer from the gynecological wards of a medical center in northern Taiwan. A total of 63 participants were divided into 2 groups: the control group (n = 30) received traditional sexual health education. The intervention group (n = 33) participated in a transtheoretical model (TTM)-based sexual health education program. Scores from self-report questionnaires for variables of knowledge, attitudes, and self-efficacy regarding sexual health collected 1 and 6 weeks after the intervention were compared with baseline scores. RESULTS: Patients who received transtheoretical model (TTM)-based sexual health education had significantly greater sexual knowledge (ß = 3.794, p < 0.01), sexual attitudes (ß = 9.226, p < 0.01), and sexual self-efficacy (ß = 17.053, p < 0.01) than those who received traditional sexual health education at 1 and 6 weeks. CONCLUSION: Our findings suggest that a one-session sexual health education using a TTM-based model can enhance sexual knowledge, attitudes, and sexual self-efficacy among patients with cervical cancer. This educational program can be translated into routine clinical practice to help patients with cervical cancer enhance their sexual health and improve confidence in their sexual well-being.


Assuntos
Modelo Transteórico , Neoplasias do Colo do Útero , Feminino , Humanos , Conhecimentos, Atitudes e Prática em Saúde , Educação Sexual , Comportamento Sexual
9.
J Clin Nurs ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886989

RESUMO

AIMS AND OBJECTIVES: To investigate the psychological distress, sexual satisfaction, and quality of life of gynaecological cancer survivors and their spouses during cancer survivorship. BACKGROUND: The survival rate of patients with cancer is increasing owing to advances in medical treatment technology. Spouses are the closest companions of gynaecological cancer survivors. Patients with gynaecological cancer and their spouses face different situations and challenges after experiencing cancer invasion. DESIGN: Questionnaire-based cross-sectional study. METHODS: Convenience sampling was employed, and 180 participants, including patients with gynaecological cancer and their spouses, were enrolled. A structured questionnaire was used to investigate the psychological distress, sexual satisfaction, and quality of life of gynaecological cancer survivors and their spouses during acute, extended, and permanent survivorship. The STROBE checklist guided the study preparation. RESULTS: For gynaecological cancer survivors and their spouses, (1) severe psychological distress was present during acute survivorship, with anxiety extending until permanent survivorship; (2) no significant differences were observed in pre- and post-treatment sexual satisfaction, although pre-treatment sexual satisfaction was higher than post-treatment sexual satisfaction in all three cancer survivorship stages and (3) quality of life decreased during acute survivorship and gradually improved with time. CONCLUSIONS: Psychological distress, sexual satisfaction and quality of life of gynaecological cancer survivors and their spouses worsened during acute survivorship and improved over time until permanent survivorship. RELEVANCE TO CLINICAL PRACTICE: Gynaecological cancer survivors and their spouses experience anxiety and depression from diagnosis confirmation until permanent survivorship (>5 years survival). Therefore, clinical nurses' sensitivity to emotional distress in cancer survivors and their spouses can be improved and a consistent and routine evaluation method has been established for the early detection of such emotional distress. The results of this study can provide a reference for clinical healthcare professionals and contribute to a better quality of care.

10.
Nano Lett ; 23(6): 2107-2113, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36881543

RESUMO

Layered transition-metal dichalcogenides down to the monolayer (ML) limit provide a fertile platform for exploring charge-density waves (CDWs). Here, we experimentally unveil the richness of the CDW phases in ML-NbTe2 for the first time. Not only the theoretically predicted 4 × 4 and 4 × 1 phases but also two unexpected 28×28 and 19×19 phases are realized. For such a complex CDW system, we establish an exhaustive growth phase diagram via systematic efforts in the material synthesis and scanning tunneling microscope characterization. Moreover, the energetically stable phase is the larger-scale order (19×19), which is surprisingly in contradiction to the prior prediction (4 × 4). These findings are confirmed using two different kinetic pathways: i.e., direct growth at proper growth temperatures (T) and low-T growth followed by high-T annealing. Our results provide a comprehensive diagram of the "zoo" of CDW orders in ML-NbTe2.

11.
Nano Lett ; 23(19): 8833-8841, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37726204

RESUMO

Moiré superlattices induced by twisted van der Waals (vdW) heterostructures or homostructures have recently gained significant attention due to their potential to generate exotic strong-correlation electronic and phonon phenomena. However, the lack of dynamic tuning for interlayer coupling of moiré superlattices hinders a thorough understanding and development of the moiré correlation state. Here, we present a dynamic tuning method for twisted WSe2/WSe2 homobilayers using a diamond anvil cell (DAC). We demonstrate the powerful tuning of interlayer coupling and observe an enhanced response to pressure for interlayer breathing modes and the rapid descent of indirect excitons in twisted WSe2/WSe2 homobilayers. Our findings indicate that the introduction of a moiré superlattice for WSe2 bilayers gives rise to hybridized excitons, which lead to the different pressure-evolution exciton behaviors compared to natural WSe2 bilayers. Our results provide a novel understanding of moiré physics and offer an effective method to tune interlayer coupling of moiré superlattices.

12.
Aesthetic Plast Surg ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995348

RESUMO

BACKGROUND: In Asia, the demand for cosmetic facial treatments has surged due to technological advancements, increased social acceptability, and affordability. Poly-L-lactic acid (PLLA) fillers, known for their biocompatibility and biodegradability, have emerged as a popular choice for facial contouring, yet studies specifically addressing their use in Asian populations are scarce. METHODS: This retrospective study examined 30 Chinese patients who underwent facial contouring with PLLA fillers, focusing on product composition, injection techniques, and safety measures. A comprehensive clinical evaluation was performed, including the Global Aesthetic Improvement Scale (GAIS) and Global Impression of Change Scale (GICS) for effectiveness and patient satisfaction, respectively. RESULTS: No significant difference in GAIS scores was observed between injectors and blinded evaluators over a 12-month period, indicating consistent effectiveness. Patient satisfaction remained high, with GICS scores reflecting positive outcomes. The safety profile was favorable, with no serious adverse events reported. The study highlighted the importance of anatomical knowledge to avoid complications, particularly in areas prone to blindness. CONCLUSIONS: PLLA fillers offer a safe, effective option for facial contour correction in the Asian population, achieving high patient satisfaction and maintaining results over time. The study underscores the need for tailored approaches in cosmetic procedures for Asians, considering their unique facial structures and aesthetic goals. Further research with larger, multicenter cohorts is recommended to validate these findings and explore long-term effects. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

13.
J Am Chem Soc ; 145(2): 1301-1309, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36579888

RESUMO

Various transition-metal trichalcogenides (TMTC) show unique electronic properties, such as metal-insulator transition, topological insulator, and even superconducting transition. Currently, almost all metallic TMTC compounds can show superconductivity either at ambient pressure or at high pressure. However, most TMTC compounds are semiconductors and even insulators. Does superconductivity exist in any non-metallic TMTC compound by artificial manipulation? In this work, the electronic behavior of highly insulating HfS3 has been manipulated in terms of pressure. HfS3 undergoes an insulator-to-semiconductor transition near 17 GPa with a band gap reduction of ∼1 eV. Optical absorption, Raman spectroscopy, and X-ray diffraction measurements provide consistent results, suggesting the structural origin of the electronic transition. Upon further compression, HfS3 becomes a superconductor without further structural transition. The superconducting transition occurs as early as 50.6 GPa, and the Tc reaches 8.1 K at 121 GPa, which sets a new record for TMTCs. This work reveals that all TMTCs may be superconductors and opens a new avenue to explore the abundant emergent phenomena in the TMTC material family.

14.
Biochem Biophys Res Commun ; 682: 199-206, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37826943

RESUMO

Although accumulating evidence has revealed that autophagy inhibition contributes to the development of pathological cardiac hypertrophy, the mechanisms leading to declined autophagy activity in the hypertrophic heart remain to be elucidated. Exosomes are known to be important mediators of intercellular communication, and the involvement of exosomes in cardiovascular abnormities has attracted increasing attentions. Cardiac fibroblasts (CFs) are the most abundant cell type in the heart. Here, we investigated the potential role of CFs-derived exosomes in regulating cardiomyocyte hypertrophy and autophagy. Exosomes from rat CFs treated with angiotensin II (Ang II-CFs-exosomes) were collected and characterized. Our experiments showed that these exosomes could induce hypertrophic responses and impair autophagy activity in primary neonatal rat cardiomyocytes (NRCMs). Ang II-CFs-exosomes blocked the autophagic flux of NRCMs via inhibiting the formation of autolysosomes. Moreover, the pro-hypertrophic effects and autophagy inhibition induced by Ang II-CFs-exosomes was validated in mice receiving injection of the exosomes. These findings highlight a novel role of Ang II-CFs-exosomes in suppressing cardiomyocyte autophagy, which may help to better understand the pathogenesis of cardiac hypertrophy.


Assuntos
Exossomos , Miócitos Cardíacos , Ratos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Angiotensina II/metabolismo , Exossomos/metabolismo , Cardiomegalia/metabolismo , Autofagia , Fibroblastos/metabolismo
15.
Biochem Biophys Res Commun ; 661: 64-74, 2023 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-37087800

RESUMO

Myocardial infarction (MI) contributes to an increased risk of incident heart failure and sudden death, but there is still a lack of effective treatment in clinic. Recently, growing evidence has indicated that abnormal expression of microRNAs (miRNAs) plays a crucial role in cardiovascular diseases. In this research, the involvement of miRNA-214-3p in MI was explored. A mouse model of MI was established by ligation of the left anterior descending coronary artery, and primary cultures of neonatal rat cardiomyocytes (NRCMs) were submitted to hypoxic treatment to stimulate cellular injury in vitro. Our results showed that miR-214-3p level was significantly upregulated in the infarcted region of mouse hearts and in NRCMs exposed to hypoxia, accompanying with an obvious elevation of ferroptosis. Inhibition of miR-214-3p by antagomir injection improved cardiac function, decreased infarct size, and attenuated iron accumulation and oxidant stress in myocardial tissues. MiR-214-3p could also promote ferroptosis and cellular impairments in NRCMs, while miR-214-3p inhibitor effectively protected cells from hypoxia. Furthermore, dual luciferase reporter gene assay revealed that malic enzyme 2 (ME2) is a direct target of miR-214-3p. In cardiomyocytes, overexpression of ME2 ameliorated the detrimental effects and excessive ferroptosis induced by miR-214-3p mimic, whereas ME2 depletion compromised the protective role of miR-214-3p inhibitor against hypoxic injury and ferroptosis. These findings suggest that miR-214-3p contributes to enhanced ferroptosis during MI at least partially via suppressing ME2. Inhibition of miR-214-3p may be a new approach for tackling MI.


Assuntos
Ferroptose , MicroRNAs , Infarto do Miocárdio , Animais , Camundongos , Ratos , Apoptose , Hipóxia/metabolismo , MicroRNAs/genética , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
16.
Small ; 19(26): e2207988, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36938893

RESUMO

The exploration of moiré superlatticesholds promising potential to uncover novel quantum phenomena emerging from the interplay of atomic structure and electronic correlation . However, the impact of the moiré potential modulation on the number of twisted layers has yet to be experimentally explored. Here, this work synthesizes a twisted WSe2 homotrilayer using a dry-transfer method and investigates the enhancement of the moiré potential with increasing number of twisted layers. The results of the study reveal the presence of multiple exciton resonances with positive or negative circularly polarized emission in the WSe2 homostructure with small twist angles, which are attributed to the excitonic ground and excited states confined to the moiré potential. The distinct g-factor observed in the magneto-optical spectroscopy is also shown to be a result of the confinement of the exciton in the moiré potential. The moiré potential depths of the twisted bilayer and trilayer homostructures are found to be 111 and 212 meV, respectively, an increase of 91% from the bilayer structure. These findings demonstrate that the depth of the moiré potential can be manipulated by adjusting the number of stacked layers, providing a promising avenue for exploration into highly correlated quantum phenomena.

17.
Opt Lett ; 48(9): 2393-2396, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126281

RESUMO

Monolayer transition metal dichalcogenides (TMDs) have a crystalline structure with broken spatial inversion symmetry, making them promising candidates for valleytronic applications. However, the degree of valley polarization is usually not high due to the presence of intervalley scattering. Here, we use the nanoindentation technique to fabricate strained structures of WSe2 on Au arrays, thus demonstrating the generation and detection of strained localized excitons in monolayer WSe2. Enhanced emission of strain-localized excitons was observed as two sharp photoluminescence (PL) peaks measured using low-temperature PL spectroscopy. We attribute these emerging sharp peaks to excitons trapped in potential wells formed by local strains. Furthermore, the valley polarization of monolayer WSe2 is modulated by a magnetic field, and the valley polarization of strained localized excitons is increased, with a high value of up to approximately 79.6%. Our results show that tunable valley polarization and localized excitons can be realized in WSe2 monolayers, which may be useful for valleytronic applications.

18.
Purinergic Signal ; 19(1): 199-206, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35218451

RESUMO

Inflammation is one of the potential factors to cause the damage of ocular surface in dry eye disease (DED). Increasing evidence indicated that purinergic A1, A2A, A3, P2X4, P2X7, P2Y1, P2Y2, and P2Y4 receptors play an important role in the regulation of inflammation in DED: A1 adenosine receptor (A1R) is a systemic pro-inflammatory factor; A2AR is involved in the activation of the MAPK/NF-kB pathway; A3R combined with inhibition of adenylate cyclase and regulation of the mitogen-activated protein kinase (MAPK) pathway leads to regulation of transcription; P2X4 promotes receptor-associated activation of pro-inflammatory cytokines and inflammatory vesicles; P2X7 promotes inflammasome activation and release of pro-inflammatory cytokines IL-1ß and IL-18; P2Y receptors affect the phospholipase C(PLC)/IP3/Ca2+ signaling pathway and mucin secretion. These suggested that purinergic receptors would be promising targets to control the inflammation of DED in the future.


Assuntos
Síndromes do Olho Seco , Receptores Purinérgicos , Humanos , Receptores Purinérgicos/metabolismo , Inflamação , Receptores Purinérgicos P1/metabolismo , Citocinas/metabolismo , Trifosfato de Adenosina/metabolismo , Receptores Purinérgicos P2X7
19.
Bioorg Med Chem ; 78: 117152, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36599264

RESUMO

The bromodomain-containing protein 4 (BRD4) has gained growing interest as an effective drug target for the treatment of hepatocellular carcinoma (HCC). Herein, we designed and synthesized a series of quinoxalinone derivatives as BRD4 inhibitors via scaffold hopping. The representative compound X9 showed potent BRD4 inhibitory activity (with IC50 = 82.3 nM), and preferable antiproliferative activity against HepG2 cells (with IC50 = 1.13 ± 0.07 µM), as well as less toxicity against GES-1 cells (with IC50 = 57.24 ± 5.46 µM). Furthermore, compound X9 dose-dependently inhibited colony formation and blocked the migration of HepG2 cells by down-regulating the expression of Snail and MMP-9 while up-regulating the E-cadherin and Occludin. Besides, compound X9 efficiently down-regulated the expression of c-Myc in HepG2 cells, induced apoptosis, and arrested at G0/G1 phase. In total, quinoxalinone was a potential core as BRD4 inhibitor and compound X9 might be effective for liver cancer therapy.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas Nucleares/metabolismo , Relação Estrutura-Atividade , Carcinoma Hepatocelular/tratamento farmacológico , Desenho de Fármacos , Neoplasias Hepáticas/tratamento farmacológico , Fatores de Transcrição , Proliferação de Células , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Ciclo Celular/metabolismo
20.
Bioorg Chem ; 133: 106412, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36773456

RESUMO

The PI3K/AKT/mTOR signaling pathway is one of the most common abnormal activation pathways in tumor cells, and has associated with multiple functions such as tumor cell growth, proliferation, migration, invasion, and tumor angiogenesis. Here, a series of 3-amino-1H-indazole derivatives were synthesized, and their antiproliferative activities against HT-29, MCF-7, A-549, HepG2 and HGC-27 cells were evaluated. Among them, W24 exhibited the broad-spectrum antiproliferative activity against four cancer cells with IC50 values of 0.43-3.88 µM. Mechanism studies revealed that W24 inhibited proliferation by affecting the DNA synthesis, induced G2/M cell cycle arrest and apoptosis by regulating Cyclin B1, BAD and Bcl-xL, meanwhile induced the change of intracellular ROS and mitochondrial membrane potential in HGC-27 cells. Moreover, W24 inhibited the migration and invasion of HGC-27 cells by decreasing EMT pathway related proteins and reducing the mRNA expression levels of Snail, Slug and HIF-1α. Furthermore, W24 displayed low tissue toxicity profile and good pharmacokinetic properties in vivo. Therefore, 3-amino-1H-indazole derivatives might serve as a new scaffold for the development of PI3K/AKT/mTOR inhibitor and anti-gastric cancer reagent.


Assuntos
Indazóis , Neoplasias , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Indazóis/química , Indazóis/farmacologia
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