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1.
Genes (Basel) ; 15(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39062632

RESUMO

Cytochrome P450 (CYP) is a crucial oxidoreductase enzyme that plays a significant role in plant defense mechanisms. In this study, a specific cytochrome P450 gene (MnCYP710A11) was discovered in mulberry (Morus notabilis). Bioinformatic analysis and expression pattern analysis were conducted to elucidate the involvement of MnCYP710A11 in combating Botrytis cinerea infection. After the infection of B. cinerea, there was a notable increase in the expression of MnCYP710A11. MnCYP710A11 is overexpressed in Arabidopsis and mulberry and strongly reacts to B. cinerea. The overexpression of the MnCYP710A11 gene in Arabidopsis and mulberry led to a substantial enhancement in resistance against B. cinerea, elevated catalase (CAT) activity, increased proline content, and reduced malondialdehyde (MDA) levels. At the same time, H2O2 and O2- levels in MnCYP710A11 transgenic Arabidopsis were decreased, which reduced the damage of ROS accumulation to plants. Furthermore, our research indicates the potential involvement of MnCYP710A11 in B. cinerea resistance through the modulation of other resistance-related genes. These findings establish a crucial foundation for gaining deeper insights into the role of cytochrome P450 in mulberry plants.


Assuntos
Arabidopsis , Botrytis , Sistema Enzimático do Citocromo P-450 , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Morus , Doenças das Plantas , Proteínas de Plantas , Botrytis/patogenicidade , Arabidopsis/genética , Arabidopsis/microbiologia , Morus/genética , Morus/microbiologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo
2.
Br J Pharmacol ; 181(17): 3019-3038, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38961617

RESUMO

ß-arrestin2, a member of the arrestin family, mediates the desensitization and internalization of most G protein-coupled receptors (GPCRs) and functions as a scaffold protein in signalling pathways. Previous studies have demonstrated that ß-arrestin2 expression is dysregulated in malignant tumours, fibrotic diseases, cardiovascular diseases and metabolic diseases, suggesting its pathological roles. Transcription and post-transcriptional modifications can affect the expression of ß-arrestin2. Furthermore, post-translational modifications, such as phosphorylation, ubiquitination, SUMOylation and S-nitrosylation affect the cellular localization of ß-arrestin2 and its interaction with downstream signalling molecules, which further regulate the activity of ß-arrestin2. This review summarizes the structure and function of ß-arrestin2 and reveals the mechanisms involved in the regulation of ß-arrestin2 at multiple levels. Additionally, recent studies on the role of ß-arrestin2 in some major diseases and its therapeutic prospects have been discussed to provide a reference for the development of drugs targeting ß-arrestin2.


Assuntos
beta-Arrestina 2 , Humanos , beta-Arrestina 2/metabolismo , Animais , Transdução de Sinais , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Processamento de Proteína Pós-Traducional , Doenças Cardiovasculares/metabolismo
3.
Nat Commun ; 15(1): 6235, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043689

RESUMO

The interaction between lattice vibrations and electrons plays a key role in various aspects of condensed matter physics - including electron hydrodynamics, strange metal behavior, and high-temperature superconductivity. In this study, we present systematic investigations using Raman scattering and angle-resolved photoemission spectroscopy (ARPES) to examine the phononic and electronic subsystems of the topological superconductor candidate 2M-WS2. Raman scattering exhibits an anomalous nonmonotonic temperature dependence of phonon linewidths, indicative of strong phonon-electron scattering over phonon-phonon scattering. The ARPES results demonstrate pronounced dispersion anomalies (kinks) at multiple binding energies within both bulk and topological surface states, indicating a robust and mode-selective coupling between the electronic states and various phonon modes. These experimental findings align with previous calculations of the Eliashberg function, providing a deeper understanding of the highest superconducting transition temperature observed in 2M-WS2 (8.8 K) among all transition metal dichalcogenides as induced by electron-phonon coupling. Furthermore, our results may offer valuable insights into other properties of 2M-WS2 and guide the search for high-temperature topological superconductors.

4.
Environ Int ; 189: 108794, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38833876

RESUMO

Indoor semivolatile organic compounds (SVOCs) pose a substantial threat to human health. However, identifying the sources of these emissions has been challenging owing to the scarcity of convenient and practical on-site methodologies. Herein, a novel method for source screening was proposed using aluminum silicate sampling strips to adsorb SVOCs from the surface air of indoor materials. The adsorbed SVOC levels indicate the emission intensity of these materials into indoor environments. Additionally, compact sampling strips can be readily fixed to any vertical surface using a static sticker, facilitating the characterization of various materials in practical settings. Laboratory-simulated experiments demonstrated the capability of the proposed method to differentiate between source and non-source materials within a 10-cm distance in the same space. In practical scenarios, the primary emission sources identified via this method exhibited a consistent correlation with the contents of the corresponding materials obtained from the traditional solvent-extraction method. As the adsorbed SVOCs were directly transferred to a GC-MS through thermal desorption instead of the solvent-extraction procedure, the proposed method demonstrated several-fold improvements in analytical sensitivity and efficiency. Using this versatile screening technique, some emerging and important SVOC species were identified within specific indoor materials. Eliminating these sources has been demonstrated as an effective approach to mitigate SVOC pollution. Overall, the proposed method offers a powerful tool for managing indoor pollutants and safeguarding human health.


Assuntos
Poluição do Ar em Ambientes Fechados , Monitoramento Ambiental , Compostos Orgânicos Voláteis , Poluição do Ar em Ambientes Fechados/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Poluentes Atmosféricos/análise , Humanos
5.
Adv Sci (Weinh) ; : e2308443, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922803

RESUMO

Tissue engineering has demonstrated its efficacy in promoting tissue regeneration, and extensive research has explored its application in rotator cuff (RC) tears. However, there remains a paucity of research translating from bench to clinic. A key challenge in RC repair is the healing of tendon-bone interface (TBI), for which bioactive materials suitable for interface repair are still lacking. The umbilical cord (UC), which serves as a vital repository of bioactive components in nature, is emerging as an important source of tissue engineering materials. A minimally manipulated approach is used to fabricate UC scaffolds that retain a wealth of bioactive components and cytokines. The scaffold demonstrates the ability to modulate the TBI healing microenvironment by facilitating cell proliferation, migration, suppressing inflammation, and inducing chondrogenic differentiation. This foundation sets the stage for in vivo validation and clinical translation. Following implantation of UC scaffolds in the canine model, comprehensive assessments, including MRI and histological analysis confirm their efficacy in inducing TBI reconstruction. Encouraging short-term clinical results further suggest the ability of UC scaffolds to effectively enhance RC repair. This investigation explores the mechanisms underlying the promotion of TBI repair by UC scaffolds, providing key insights for clinical application and translational research.

6.
Dalton Trans ; 53(28): 11787-11799, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38940617

RESUMO

The extraction and recovery of valuable metals from various spent catalysts via bioleaching represents a green, low-carbon and eco-friendly process. However, the pulp density of spent catalysts is usually 1.0% or lower owing to their toxicity, denoting low process capacity and poor practical potential. In this study, an intensified bioleaching strategy was used for the first time to promote the release efficiencies of both Co and Mo from a spent Co-Mo catalyst at a high pulp density of 10% by supplementing extracellular polymeric substances (EPSs). The results showed that the addition of 0.6 g L-1 EPSs harvested a maximum release of 73.6% for Co and 72.5% for Mo after 9 days of contact, with an evident elevation of 22.6% for Co and 24.4% for Mo, in contrast to no addition, respectively. The added EPS not only promoted the growth of plankton cells to produce more active molecules but also boosted the adhesion of leaching cells to the spent catalyst to form stable aggregates. Moreover, the resulting aggregates allowed for the gathering and confinement of the active small molecules, including Fe3+ and Fe2+, inside the micro-areas between the spent catalysts and the cells for quick electronic transfer as an interface oxidation/reduction reaction to free both Co and Mo from the spent catalyst.


Assuntos
Cobalto , Matriz Extracelular de Substâncias Poliméricas , Molibdênio , Catálise , Cobalto/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Matriz Extracelular de Substâncias Poliméricas/química , Molibdênio/química , Monóxido de Carbono/química
7.
Biol Pharm Bull ; 47(7): 1248-1254, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38866477

RESUMO

Ethanol (alcohol) is a risk factor that contributes to non-communicable diseases. Chronic abuse of ethanol is toxic to both the heart and overall health, and even results in death. Ethanol and its byproduct acetaldehyde can harm the cardiovascular system by impairing mitochondrial function, causing oxidative damage, and reducing contractile proteins. Endothelial cells are essential components of the cardiovascular system, are highly susceptible to ethanol, either through direct or indirect exposure. Thus, protection against endothelial injury is of great importance for persons who chronic abuse of ethanol. In this study, an in vitro model of endothelial injury was created using ethanol. The findings revealed that a concentration of 20.0 mM of ethanol reduced cell viability and Bcl-2 expression, while increasing cell apoptosis, intracellular reactive oxygen species (ROS) levels, mitochondrial depolarization, and the expression of Bax and cleaved-caspase-3 in endothelial cells. Further study showed that ethanol promoted nuclear translocation of nuclear factor kappa B (NF-κB), increased the secretion of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 in the culture medium, and inhibited nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling pathway. The aforementioned findings suggest that ethanol has a harmful impact on endothelial cells. Nevertheless, the application of epigallocatechin-3-gallate (EGCG) to the cells can effectively mitigate the detrimental effects of ethanol on endothelial cells. In conclusion, EGCG alleviates ethanol-induced endothelial injury partly through alteration of NF-κB translocation and activation of the Nrf2 signaling pathway. Therefore, EGCG holds great potential in safeguarding individuals who chronically abuse ethanol from endothelial dysfunction.


Assuntos
Catequina , Etanol , Fator 2 Relacionado a NF-E2 , NF-kappa B , Transdução de Sinais , Etanol/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Catequina/uso terapêutico , NF-kappa B/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
8.
Clin Transl Allergy ; 14(6): e12359, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38860615

RESUMO

OBJECTIVE: This work endeavored to examine the correlation between dietary choline intake and the odds of asthma, utilizing data from the National Health and Nutrition Examination Survey (NHANES). METHODS: Aggregated data from seven cycles (2005-2018) in the NHANES database were utilized. The independent variable was dietary choline intake, and the dependent variable was asthma. The weighted logistic regression method was used to construct a model reflecting the relationship between these two factors. This work employed stratified analysis without adjusting for confounding factors and subgroup analysis with adjusted confounding factors to mine the association between dietary choline intake and asthma. Additionally, restricted cubic spline analysis examined nonlinear associations of the two in age subgroups. RESULTS: Forty five thousand and seven hundreds ninety seven samples were included here. The model indicating the relationship between dietary choline intake and asthma was constructed (OR: 0.86, 95% CI: 0.79-0.93, p < 0.001). Stratified analysis indicated that the interaction terms of age (p < 0.001) and body mass index (BMI) (p = 0.002) with dietary choline intake significantly influenced the relationship model. In the adjusted models, accounting for demographic characteristics, poverty impact ratio, BMI, exposure to environmental tobacco smoke, and total energy intake, an increase in dietary choline intake significantly reduced the odds of asthma (OR: 0.79, 95% CI: 0.72-0.88, p < 0.001). Subgroup analyses based on age and BMI revealed a significant negative correlation between dietary choline intake and the odds of asthma in the adult population (OR: 0.76, 95% CI: 0.67-0.86, p < 0.001), as well as in individuals with a BMI between 25 and 30 kg/m2 (OR: 0.79, 95% CI: 0.63-0.99, p = 0.042), and those with a BMI >30 kg/m2 (OR: 0.73, 95% CI: 0.60-0.89, p = 0.002). CONCLUSION: Dietary choline intake was significantly inversely correlated with asthma prevalence, especially in adults and overweight/obese individuals, suggesting that increasing choline intake may reduce asthma risk. Further research is needed to explore this relationship and provide tailored dietary recommendations for different age and BMI groups to enhance asthma prevention and management.

9.
Sci Total Environ ; 946: 174154, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38942310

RESUMO

In this study, the planetary ball milling with CaO addition was used to remediate lindane-contaminated soil. Based on Hertzian theory, a mathematical model was proposed to simulate the trajectory of grinding ball and the local energy transfer during a planetary operation at the disk rotation velocities of 150-250 rpm. Besides, the influence of different parameters on lindane removal in soil was investigated, whose results showed that disk rotation velocity and reagent-to-soil ratio had a positive effect, while soil moisture, initial concentration of lindane, and mass of polluted soil demonstrated a negative influence. The mechanochemical method exhibited a higher degradation performance at 3 wt% CaO addition, and a disk rotation velocity of 250 rpm. Active species generated by ball collisions in the presence of CaO, especially superoxide (·O2-) demonstrated a significant role in participating in the lindane conversion. In combination with GCMS and XPS analysis, the proposed model provides insight into mechanochemical remediation process from physical and chemical perspectives, which mainly includes four main steps: mixing, inducing, chemical reaction, and structure destruction.

10.
Nanomedicine ; 60: 102758, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852881

RESUMO

The clinical application of tumor necrosis factor-α (TNF-α) is limited by its short half-life, subeffective concentration in the targeted area and severe systemic toxicity. In this study, the recombinant polypeptide S4-TNF-α was constructed and coupled with chitosan-modified superparamagnetic iron oxide nanoparticles (S4-TNF-α-SPIONs) to achieve pH-sensitive controlled release and active tumor targeting activity. The isoelectric point (pI) of S4-TNF-α was reconstructed to approach the pH of the tumor microenvironment. The negative-charge S4-TNF-α was adsorbed to chitosan-modified superparamagnetic iron oxide nanoparticles (CS-SPIONs) with a positive charge through electrostatic adsorption at physiological pH. The acidic tumor microenvironment endowed S4-TNF-α with a zero charge, which accelerated S4-TNF-α release from CS-SPIONs. Our studies showed that S4-TNF-α-SPIONs displayed an ideal pH-sensitive controlled release capacity and improved antitumor effects. Our study presents a novel approach to enhance the pH-sensitive controlled-release of genetically engineered drugs by adjusting their pI to match the pH of the tumor microenvironment.


Assuntos
Preparações de Ação Retardada , Fator de Necrose Tumoral alfa , Fator de Necrose Tumoral alfa/metabolismo , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Humanos , Animais , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Camundongos , Nanopartículas Magnéticas de Óxido de Ferro/química , Quitosana/química , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C
11.
Nat Commun ; 15(1): 4512, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802369

RESUMO

In higher plants, mature male gametophytes have distinct apertures. After pollination, pollen grains germinate, and a pollen tube grows from the aperture to deliver sperm cells to the embryo sac, completing fertilization. In rice, the pollen aperture has a single-pore structure with a collar-like annulus and a plug-like operculum. A crucial step in aperture development is the formation of aperture plasma membrane protrusion (APMP) at the distal polar region of the microspore during the late tetrad stage. Previous studies identified OsINP1 and OsDAF1 as essential regulators of APMP and pollen aperture formation in rice, but their precise molecular mechanisms remain unclear. We demonstrate that the Poaceae-specific OsSRF8 gene, encoding a STRUBBELIG-receptor family 8 protein, is essential for pollen aperture formation in Oryza sativa. Mutants lacking functional OsSRF8 exhibit defects in APMP and pollen aperture formation, like loss-of-function OsINP1 mutants. OsSRF8 is specifically expressed during early anther development and initially diffusely distributed in the microsporocytes. At the tetrad stage, OsSRF8 is recruited by OsINP1 to the pre-aperture region through direct protein-protein interaction, promoting APMP formation. The OsSRF8-OsINP1 complex then recruits OsDAF1 to the APMP site to co-regulate annulus formation. Our findings provide insights into the mechanisms controlling pollen aperture formation in cereal species.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Pólen/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento , Mutação , Polinização , Membrana Celular/metabolismo , Plantas Geneticamente Modificadas , Tubo Polínico/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/genética
12.
ACS Nano ; 18(21): 13662-13674, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38752487

RESUMO

Porous copper (Cu) current collectors show promise in stabilizing Li metal anodes (LMAs). However, insufficient lithiophilicity of pure Cu and limited porosity in three-dimensional (3D) porous Cu structures led to an inefficient Li-Cu composite preparation and poor electrochemical performance of Li-Cu composite anodes. Herein, we propose a porous Cu-CuZn (DG-CCZ) host for Li composite anodes to tackle these issues. This architecture features a pore size distribution and lithiophilic-lithiophobic characteristics designed in a gradient distribution from the inside to the outside of the anode structure. This dual-gradient porous Cu-CuZn exhibits exceptional capillary wettability to molten Li and provides a high porosity of up to 66.05%. This design promotes preferential Li deposition in the interior of the porous structure during battery operation, effectively inhibiting Li dendrite formation. Consequently, all cell systems achieve significantly improved cycling stability, including Li half-cells, Li-Li symmetric cells, and Li-LFP full cells. When paired synergistically with the double-coated LiFePO4 cathode, the pouch cell configured with multiple electrodes demonstrates an impressive discharge capacity of 159.3 mAh g-1 at 1C. We believe this study can inspire the design of future 3D Li anodes with enhanced Li utilization efficiency and facilitate the development of future high-energy Li metal batteries.

13.
Sci Total Environ ; 933: 173208, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38750758

RESUMO

In this study, 3,4,3',4'-tetrachlorobiphenyl (PCB77) contaminated soil was remediated by a fluidization bed dielectric barrier discharge (DBD) reactor and a fixed bed DBD reactor. The fluidized bed reactor could attain superior removal efficiency of PCB77 under same experimental parameters. In-situ discharge mode was more conducive to the degradation of PCB77 than ex-situ discharge mode due to short-lived active species existing in in-situ discharge. The influence of experimental parameters in the fluidized bed DBD reactor on the degradation of PCB77 were discussed such as electric features, gas features, soil features and initial PCB77 concentration. PCB77 removal efficiency in air discharge could reach 88.5 % after 8 min under the alkaline condition. Optical emission spectroscopy (OES) and quench tests showed that reactive oxygen species (ROS) and reactive nitrogen species (RNS) were generated in the discharge system and they both played a vital role in the degradation of PCB77. Scanning electron microscopy (SEM) results demonstrated that discharge had little effect on the morphology of soil particles. Energy dispersive spectrometer (EDS), ion chromatography (IC), and total organic carbon (TOC) results showed that the DBD could effectively mineralize and dechlorinate PCB77. The possible degradation pathway of PCB77 was inferred at the end based on the degradation products determined by gas chromatography-mass spectrometry (GC-MS).

14.
Cancer Lett ; 594: 216981, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38795761

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC), a leading cause of cancer mortality, has a complex pathogenesis involving various immune cells, including B cells and their subpopulations. Despite emerging research on the role of these cells within the tumor microenvironment (TME), the detailed molecular interactions with tumor-infiltrating immune cells (TIICs) are not fully understood. METHODS: We applied CIBERSORT to quantify TIICs and naive B cells, which are prognostic for PDAC. Marker genes from scRNA-seq and modular genes from weighted gene co-expression network analysis (WGCNA) were integrated to identify naive B cell-related genes. A prognostic signature was constructed utilizing ten machine-learning algorithms, with validation in external cohorts. We further assessed the immune cell diversity, ESTIMATE scores, and immune checkpoint genes (ICGs) between patient groups stratified by risk to clarify the immune landscape in PDAC. RESULTS: Our analysis identified 994 naive B cell-related genes across single-cell and bulk transcriptomes, with 247 linked to overall survival. We developed a 12-gene prognostic signature using Lasso and plsRcox algorithms, which was confirmed by 10-fold cross-validation and showed robust predictive power in training and real-world cohorts. Notably, we observed substantial differences in immune infiltration between patients with high and low risk. CONCLUSION: Our study presents a robust prognostic signature that effectively maps the complex immune interactions in PDAC, emphasizing the critical function of naive B cells and suggesting new avenues for immunotherapeutic interventions. This signature has potential clinical applications in personalizing PDAC treatment, enhancing the understanding of immune dynamics, and guiding immunotherapy strategies.


Assuntos
Biomarcadores Tumorais , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Microambiente Tumoral , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/mortalidade , Prognóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/mortalidade , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Linfócitos B/imunologia , Linfócitos do Interstício Tumoral/imunologia , Regulação Neoplásica da Expressão Gênica , Aprendizado de Máquina , Transcriptoma , Perfilação da Expressão Gênica/métodos , Masculino , Feminino
15.
Opt Lett ; 49(10): 2705-2708, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748141

RESUMO

The silicon thermo-optic switch (TOS) is one of the most fundamental and crucial blocks in large-scale silicon photonic integrated circuits (PICs). An energy-efficient silicon TOS with ultrahigh extinction ratio can effectively mitigate cross talk and reduce power consumption in optical systems. In this Letter, we demonstrate a silicon TOS based on cascading Mach-Zehnder interferometers (MZIs) with spiral thermo-optic phase shifters. The experimental results show that an ultrahigh extinction ratio of 58.8 dB is obtained, and the switching power consumption is as low as 2.32 mW/π without silicon air trench. The rise time and fall time of the silicon TOS are about 10.8 and 11.2 µs, respectively. Particularly, the figure of merit (FOM) has been improved compared with previously reported silicon TOS. The proposed silicon TOS may find potential applications in optical switch arrays, on-chip optical delay lines, etc.

16.
Nano Lett ; 24(19): 5791-5798, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695400

RESUMO

The second-order nonlinear transport illuminates a frequency-doubling response emerging in quantum materials with a broken inversion symmetry. The two principal driving mechanisms, the Berry curvature dipole and the skew scattering, reflect various information including ground-state symmetries, band dispersions, and topology of electronic wave functions. However, effective manipulation of them in a single system has been lacking, hindering the pursuit of strong responses. Here, we report on the effective manipulation of the two mechanisms in a single graphene moiré superlattice, AB-BA stacked twisted double bilayer graphene. Most saliently, by virtue of the high tunability of moiré band structures and scattering rates, a record-high second-order transverse conductivity ∼ 510 µm S V-1 is observed, which is orders of magnitude higher than any reported values in the literature. Our findings establish the potential of electrically tunable graphene moiré systems for nonlinear transport manipulations and applications.

17.
Sci Rep ; 14(1): 11799, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782981

RESUMO

To address the issues of low accuracy and slow response speed in tea disease classification and identification, an improved YOLOv7 lightweight model was proposed in this study. The lightweight MobileNeXt was used as the backbone network to reduce computational load and enhance efficiency. Additionally, a dual-layer routing attention mechanism was introduced to enhance the model's ability to capture crucial details and textures in disease images, thereby improving accuracy. The SIoU loss function was employed to mitigate missed and erroneous judgments, resulting in improved recognition amidst complex image backgrounds.The revised model achieved precision, recall, and average precision of 93.5%, 89.9%, and 92.1%, respectively, representing increases of 4.5%, 1.9%, and 2.6% over the original model. Furthermore, the model's volum was reduced by 24.69M, the total param was reduced by 12.88M, while detection speed was increased by 24.41 frames per second. This enhanced model efficiently and accurately identifies tea disease types, offering the benefits of lower parameter count and faster detection, thereby establishing a robust foundation for tea disease monitoring and prevention efforts.


Assuntos
Doenças das Plantas , Chá , Algoritmos , Camellia sinensis/classificação , Processamento de Imagem Assistida por Computador/métodos
18.
ACS Omega ; 9(20): 21768-21779, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799322

RESUMO

Thrombolytic enzymes constitute a class of proteases with antithrombotic functions. Derived from natural products and abundant in nature, certain thrombolytic enzymes, such as urokinase, earthworm kinase, and streptokinase, have been widely used in the clinical treatment of vascular embolic diseases. Fly maggots, characterized by their easy growth and low cost, are a traditional Chinese medicine recorded in the Compendium of Materia Medica. These maggots can also be used as raw material for the extraction and preparation of thrombolytic enzymes (maggot kinase). In this review, we assembled global research reports on natural thrombolytic enzymes through a literature search and reviewed the functions and structures of natural thrombolytic enzymes to provide a reference for natural thrombophilic drug screening and development.

19.
Acta Biomater ; 180: 82-103, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38621599

RESUMO

The treatment of osteoporotic bone defect remains a big clinical challenge because osteoporosis (OP) is associated with oxidative stress and high levels of reactive oxygen species (ROS), a condition detrimental for bone formation. Anti-oxidative nanomaterials such as selenium nanoparticles (SeNPs) have positive effect on osteogenesis owing to their pleiotropic pharmacological activity which can exert anti-oxidative stress functions to prevent bone loss and facilitate bone regeneration in OP. In the current study a strategy of one-pot method by introducing Poly (lactic acid-carbonate) (PDT) and ß-Tricalcium Phosphate (ß-TCP) with SeNPs, is developed to prepare an injectable, anti-collapse, shape-adaptive and adhesive bone graft substitute material (PDT-TCP-SE). The PDT-TCP-SE bone graft substitute exhibits sufficient adhesion in biological microenvironments and osteoinductive activity, angiogenic effect and anti-inflammatory as well as anti-oxidative effect in vitro and in vivo. Moreover, the PDT-TCP-SE can protect BMSCs from erastin-induced ferroptosis through the Sirt1/Nrf2/GPX4 antioxidant pathway, which, in together, demonstrated the bone graft substitute material as an emerging biomaterial with potential clinical application for the future treatment of osteoporotic bone defect. STATEMENT OF SIGNIFICANCE: Injectable, anti-collapse, adhesive, plastic and bioactive bone graft substitute was successfully synthesized. Incorporation of SeNPs with PDT into ß-TCP regenerated new bone in-situ by moderating oxidative stress in osteoporotic bone defects area. The PDT-TCP-SE bone graft substitute reduced high ROS levels in osteoporotic bone defect microenvironment. The bone graft substitute could also moderate oxidative stress and inhibit ferroptosis via Sirt1/Nrf2/GPX4 pathway in vitro. Moreover, the PDT-TCP-SE bone graft substitute could alleviate the inflammatory environment and promote bone regeneration in osteoporotic bone defect in vivo. This biomaterial has the advantages of simple synthesis, biocompatibility, anti-collapse, injectable, and regulation of oxidative stress level, which has potential application value in bone tissue engineering.


Assuntos
Regeneração Óssea , Substitutos Ósseos , Fosfatos de Cálcio , Osteoporose , Estresse Oxidativo , Estresse Oxidativo/efeitos dos fármacos , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osteoporose/patologia , Osteoporose/terapia , Osteoporose/tratamento farmacológico , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/química , Ratos Sprague-Dawley , Selênio/química , Selênio/farmacologia , Feminino , Osteogênese/efeitos dos fármacos , Poliésteres/química , Poliésteres/farmacologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos , Injeções
20.
Cancer Sci ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38685894

RESUMO

Multiple Endocrine Neoplasia 1 gene (MEN1), which is known to be a tumor suppressor gene in lung tissues, encodes a 610 amino acid protein menin. Previous research has proven that MEN1 deficiency promotes the malignant progression of lung cancer. However, the biological role of this gene in the immune microenvironment of lung cancer remains unclear. In this study, we found that programmed cell death-ligand 1 (PD-L1) is upregulated in lung-specific KrasG12D mutation-induced lung adenocarcinoma in mice, after Men1 deficiency. Simultaneously, CD8+ and CD3+ T cells are depleted, and their cytotoxic effects are suppressed. In vitro, PD-L1 is inhibited by the overexpression of menin. Mechanistically, we found that MEN1 inactivation promotes the deubiquitinating activity of COP9 signalosome subunit 5 (CSN5) and subsequently increases the level of PD-L1.

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