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1.
J Hazard Mater ; 476: 135092, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964040

RESUMO

Methylisothiazolinone (MIT) is a widely used preservative and biocide to prevent product degradation, yet its potential impact on plant growth remains poorly understood. In this study, we investigated MIT's toxic effects on Arabidopsis thaliana root growth. Exposure to MIT significantly inhibited Arabidopsis root growth, associated with reduced root meristem size and root meristem cell numbers. We explored the polar auxin transport pathway and stem cell regulation as key factors in root meristem function. Our findings demonstrated that MIT suppressed the expression of the auxin efflux carrier PIN1 and major root stem cell regulators (PLT1, PLT2, SHR, and SCR). Additionally, MIT hindered root regeneration by downregulating the quiescent center (QC) marker WOX5. Transcriptome analysis revealed MIT-induced alterations in gene expression related to oxidative stress, with physiological experiments confirming elevated reactive oxygen species (ROS) levels and increased cell death in root tips at concentrations exceeding 50 µM. In summary, this study provides critical insights into MIT's toxicity on plant root development and regeneration, primarily linked to modifications in polar auxin transport and downregulation of genes associated with root stem cell regulation.

2.
Int J Biol Macromol ; 274(Pt 2): 133446, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945337

RESUMO

Panax ginseng C.A. Mey., known for its medicinal and dietary supplement properties, primarily contains pharmacologically active ginsenosides. However, the regulatory mechanisms linking ginseng root development with ginsenoside biosynthesis are still unclear. Root meristem growth factors (RGFs) are crucial for regulating plant root growth. In our study, we identified five ginseng RGF peptide sequences from the ginseng genome and transcriptome libraries. We treated Arabidopsis and ginseng adventitious roots with exogenous Panax ginseng RGFs (PgRGFs) to assess their activities. Our results demonstrate that PgRGF1 influences gravitropic responses and reduces lateral root formation in Arabidopsis. PgRGF1 has been found to restrict the number and length of ginseng adventitious root branches in ginseng. Given the medicinal properties of ginseng, We determined the ginsenoside content and performed transcriptomic analysis of PgRGF1-treated ginseng adventitious roots. Specifically, the total ginsenoside content in ginseng adventitious roots decreased by 19.98 % and 63.71 % following treatments with 1 µM and 10 µM PgRGF1, respectively, compared to the control. The results revealed that PgRGF1 affects the accumulation of ginsenosides by regulating the expression of genes associated with auxin transportation and ginsenoside biosynthesis. These findings suggest that PgRGF1, as a peptide hormone regulator in ginseng, can modulate adventitious root growth and ginsenoside accumulation.

3.
Front Plant Sci ; 15: 1397816, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903428

RESUMO

Citrus fruits are extensively cultivated fruits with high nutritional value. The identification of distinct ripeness stages in citrus fruits plays a crucial role in guiding the planning of harvesting paths for citrus-picking robots and facilitating yield estimations in orchards. However, challenges arise in the identification of citrus fruit ripeness due to the similarity in color between green unripe citrus fruits and tree leaves, leading to an omission in identification. Additionally, the resemblance between partially ripe, orange-green interspersed fruits and fully ripe fruits poses a risk of misidentification, further complicating the identification of citrus fruit ripeness. This study proposed the YOLO-CIT (You Only Look Once-Citrus) model and integrated an innovative R-LBP (Roughness-Local Binary Pattern) method to accurately identify citrus fruits at distinct ripeness stages. The R-LBP algorithm, an extension of the LBP algorithm, enhances the texture features of citrus fruits at distinct ripeness stages by calculating the coefficient of variation in grayscale values of pixels within a certain range in different directions around the target pixel. The C3 model embedded by the CBAM (Convolutional Block Attention Module) replaced the original backbone network of the YOLOv5s model to form the backbone of the YOLO-CIT model. Instead of traditional convolution, Ghostconv is utilized by the neck network of the YOLO-CIT model. The fruit segment of citrus in the original citrus images processed by the R-LBP algorithm is combined with the background segment of the citrus images after grayscale processing to construct synthetic images, which are subsequently added to the training dataset. The experiment showed that the R-LBP algorithm is capable of amplifying the texture features among citrus fruits at distinct ripeness stages. The YOLO-CIT model combined with the R-LBP algorithm has a Precision of 88.13%, a Recall of 93.16%, an F1 score of 90.89, a mAP@0.5 of 85.88%, and 6.1ms of average detection speed for citrus fruit ripeness identification in complex environments. The model demonstrates the capability to accurately and swiftly identify citrus fruits at distinct ripeness stages in real-world environments, effectively guiding the determination of picking targets and path planning for harvesting robots.

4.
J Chem Inf Model ; 64(12): 4739-4758, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38863138

RESUMO

Despite recent success in the computational approaches of cyclic peptide design, current studies face challenges in modeling noncanonical amino acids and nonstandard cyclizations due to limited data. To address this challenge, we developed an integrated framework for the tailored design of stapled peptides (SPs) targeting the bromodomain of CREBBP (CREBBP-BrD). We introduce a powerful combination of anchored stapling and hierarchical molecular dynamics to design and optimize SPs by employing the MultiScale integrative conformational dynamics assessment (MSICDA) strategy, which involves an initial virtual screening of over 1.5 million SPs, followed by comprehensive simulations amounting to 154.54 µs across 5418 of instances. The MSICDA method provides a detailed and holistic stability view of peptide-protein interactions, systematically isolated optimized peptides and identified two leading candidates, DA#430 and DA#99409, characterized by their enhanced stability, optimized binding, and high affinity toward the CREBBP-BrD. In cell-free assays, DA#430 and DA#99409 exhibited 2- to 12-fold greater potency than inhibitor SGC-CBP30. Cell studies revealed higher peptide selectivity for cancerous versus normal cells over small molecules. DA#430 combined with (+)-JQ-1 showed promising synergistic effects. Our approach enables the identification of peptides with optimized binding, high affinity, and enhanced stability, leading to more precise and effective cyclic peptide design, thereby establishing MSICDA as a generalizable and transformative tool for uncovering novel targeted drug development in various therapeutic areas.


Assuntos
Proteína de Ligação a CREB , Simulação de Dinâmica Molecular , Proteína de Ligação a CREB/química , Proteína de Ligação a CREB/metabolismo , Proteína de Ligação a CREB/antagonistas & inibidores , Humanos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Domínios Proteicos , Conformação Proteica , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Linhagem Celular Tumoral , Ligação Proteica
5.
Sci Rep ; 14(1): 12256, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806573

RESUMO

The Transformer-based Siamese networks have excelled in the field of object tracking. Nevertheless, a notable limitation persists in their reliance on ResNet as backbone, which lacks the capacity to effectively capture global information and exhibits constraints in feature representation. Furthermore, these trackers struggle to effectively attend to target-relevant information within the search region using multi-head self-attention (MSA). Additionally, they are prone to robustness challenges during online tracking and tend to exhibit significant model complexity. To address these limitations, We propose a novel tracker named ASACTT, which includes a backbone network, feature fusion network and prediction head. First, we improve the Swin-Transformer-Tiny to enhance its global information extraction capabilities. Second, we propose an adaptive sparse attention (ASA) to focus on target-specific details within the search region. Third, we leverage position encoding and historical candidate data to develop a dynamic template updater (DTU), which ensures the preservation of the initial frame's integrity while gracefully adapting to variations in the target's appearance. Finally, we optimize the network model to maintain accuracy while minimizing complexity. To verify the effectiveness of our proposed tracker, ASACTT, experiments on five benchmark datasets demonstrated that the proposed tracker was highly comparable to other state-of-the-art methods. Notably, in the GOT-10K1 evaluation, our tracker achieved an outstanding success score of 75.3% at 36 FPS, significantly surpassing other trackers with comparable model parameters.

6.
BMC Med Genomics ; 17(1): 120, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702721

RESUMO

BACKGROUND: Sepsis ranks among the most formidable clinical challenges, characterized by exorbitant treatment costs and substantial demands on healthcare resources. Mitochondrial dysfunction emerges as a pivotal risk factor in the pathogenesis of sepsis, underscoring the imperative to identify mitochondrial-related biomarkers. Such biomarkers are crucial for enhancing the accuracy of sepsis diagnostics and prognostication. METHODS: In this study, adhering to the SEPSIS 3.0 criteria, we collected peripheral blood within 24 h of admission from 20 sepsis patients at the ICU of the Southwest Medical University Affiliated Hospital and 10 healthy volunteers as a control group for RNA-seq. The RNA-seq data were utilized to identify differentially expressed RNAs. Concurrently, mitochondrial-associated genes (MiAGs) were retrieved from the MitoCarta3.0 database. The differentially expressed genes were intersected with MiAGs. The intersected genes were then subjected to GO (Gene Ontology), and KEGG (Kyoto Encyclopedia of Genes and Genomes) analyses and core genes were filtered using the PPI (Protein-Protein Interaction) network. Subsequently, relevant sepsis datasets (GSE65682, GSE28750, GSE54514, GSE67652, GSE69528, GSE95233) were downloaded from the GEO (Gene Expression Omnibus) database to perform bioinformatic validation of these core genes. Survival analysis was conducted to assess the prognostic value of the core genes, while ROC (Receiver Operating Characteristic) curves determined their diagnostic value, and a meta-analysis confirmed the accuracy of the RNA-seq data. Finally, we collected 5 blood samples (2 normal controls (NC); 2 sepsis; 1 SIRS (Systemic Inflammatory Response Syndrome), and used single-cell sequencing to assess the expression levels of the core genes in the different blood cell types. RESULTS: Integrating high-throughput sequencing with bioinformatics, this study identified two mitochondrial genes (COX7B, NDUFA4) closely linked with sepsis prognosis. Survival analysis demonstrated that patients with lower expression levels of COX7B and NDUFA4 exhibited a higher day survival rate over 28 days, inversely correlating with sepsis mortality. ROC curves highlighted the significant sensitivity and specificity of both genes, with AUC values of 0.985 for COX7B and 0.988 for NDUFA4, respectively. Meta-analysis indicated significant overexpression of COX7B and NDUFA4 in the sepsis group in contrast to the normal group (P < 0.01). Additionally, single-cell RNA sequencing revealed predominant expression of these core genes in monocytes-macrophages, T cells, and B cells. CONCLUSION: The mitochondrial-associated genes (MiAGs) COX7B and NDUFA4 are intimately linked with the prognosis of sepsis, offering potential guidance for research into the mechanisms underlying sepsis.


Assuntos
Sepse , Humanos , Sepse/genética , Sepse/diagnóstico , Sepse/sangue , Masculino , Análise de Célula Única , Genes Mitocondriais , Feminino , Análise de Sequência de RNA , Pessoa de Meia-Idade , Biomarcadores/sangue , Prognóstico , Estudos de Casos e Controles , Idoso
7.
Bioengineering (Basel) ; 11(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38671802

RESUMO

Nanobodies have emerged as promising tools in biomedicine due to their single-chain structure and inherent stability. They generally have convex paratopes, which potentially prefer different epitope sites in an antigen compared to traditional antibodies. In this study, a synthetic phage display nanobody library was constructed and used to identify nanobodies targeting a tumor-associated antigen, the human B7-H3 protein. Combining next-generation sequencing and single-clone validation, two nanobodies were identified to specifically bind B7-H3 with medium nanomolar affinities. Further characterization revealed that these two clones targeted a different epitope compared to known B7-H3-specific antibodies, which have been explored in clinical trials. Furthermore, one of the clones, dubbed as A6, exhibited potent antibody-dependent cell-mediated cytotoxicity (ADCC) against a colorectal cancer cell line with an EC50 of 0.67 nM, upon conversion to an Fc-enhanced IgG format. These findings underscore a cost-effective strategy that bypasses the lengthy immunization process, offering potential rapid access to nanobodies targeting unexplored antigenic sites.

8.
Adv Mater ; 36(24): e2313860, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38529666

RESUMO

Ion migration-induced intrinsic instability and large-area fabrication pose a tough challenge for the commercial deployment of perovskite photovoltaics. Herein, an interface heterojunction and metal electrode stabilization strategy is developed by suppressing ion migration via managing lead-based imperfections. After screening a series of cations and nonhalide anions, the ideal organic salt molecule dimethylammonium trifluoroacetate (DMATFA) consisting of dimethylammonium (DMA+) cation and trifluoroacetate (TFA-) anion is selected to manipulate the surface of perovskite films. DMA+ enables the conversion of active excess and/or unreacted PbI2 into stable new phase DMAPbI3, inhibiting photodecomposition of PbI2 and ion migration. Meanwhile, TFA- can suppress iodide ion migration through passivating undercoordinated Pb2+ and/or iodide vacancies. DMA+ and TFA- synergistically stabilize the heterojunction interface and silver electrode. The DMATFA-treated inverted perovskite solar cells and modules achieve a maximum efficiency of 25.03% (certified 24.65%, 0.1 cm2) and 20.58% (63.74 cm2), respectively, which is the record efficiency ever reported for the devices based on vacuum flash evaporation technology. The DMATFA modification results in outstanding operational stability, as evidenced by maintaining 91% of its original efficiency after 1520 h of maximum power point continuous tracking.

9.
ACS Appl Mater Interfaces ; 16(5): 5486-5503, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38284176

RESUMO

Cranial bone defects remain a major clinical challenge, increasing patients' life burdens. Tricarboxylic acid (TCA) cycle metabolites play crucial roles in facilitating bone tissue regeneration. However, the development of TCA cycle metabolite-modified biomimetic grafts for skull bone regeneration still needs to be improved. The mechanism underlying the release of TCA cycle metabolites from biomaterials in regulating immune responses and mesenchymal stem cell (MSC) fate (migration and differentiation) remains unknown. Herein, this work constructs biomimetic hydrogels composed of gelatin and chitosan networks covalently cross-linked by genipin (CGG hydrogels). A series of TCA cycle metabolite-coordinated CGG hydrogels with strong mechanical and antiswelling performances are subsequently developed. Remarkably, the citrate (Na3Cit, Cit)-coordinated CGG hydrogels (CGG-Cit hydrogels) with the highest mechanical modulus and strength significantly promote skull bone regeneration in rat and murine cranial defects. Mechanistically, using a transgenic mouse model, bulk RNA sequencing, and single-cell RNA sequencing, this work demonstrates that CGG-Cit hydrogels promote Gli1+ MSC migration via neutrophil-secreted oncostatin M. Results also indicate that citrate improves osteogenesis via enhanced histone H3K9 acetylation on osteogenic master genes. Taken together, the immune microenvironment- and MSC fate-regulated CGG-Cit hydrogels represent a highly efficient and facile approach toward skull bone tissue regeneration with great potential for bench-to-bedside translation.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Ratos , Camundongos , Animais , Histonas , Ciclo do Ácido Cítrico , Acetilação , Neutrófilos/metabolismo , Regeneração Óssea , Crânio/metabolismo , Diferenciação Celular , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Citratos
10.
J Biomol Struct Dyn ; 42(6): 2809-2824, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37194299

RESUMO

Cyclic peptides (CPs) are a promising class of drugs because of their high biological activity and specificity. However, the design of CP remains challenging due to their conformational flexibility and difficulties in designing stable binding conformation. Herein, we present a high-throughput MD screening (HTMDS) process for the iterative design of stable CP binders with a combinatorial CP library composed of canonical and non-canonical amino acids. As a proof of concept, we apply our methods to design CP inhibitors for the bromodomain (BrD) of ATAD2B. 698,800 CP candidates with a total of 25,570 ns MD simulations were performed to study the protein-ligand binding interactions. The binding free energies (ΔGbind) estimated by MM/PBSA approach for eight lead CP designs were found to be low. CP-1st.43 was the best CP candidate with an estimated ΔGbind of -28.48 kcal/mol when compared to the standard inhibitor C-38 which has been experimentally validated and shown to exhibit ΔGbind of -17.11 kcal/mol. The major contribution of binding sites for BrD of ATAD2B involved the hydrogen-bonding anchor within the Aly-binding pocket, salt bridging, and hydrogen-bonding mediated stabilization of the ZA loop and BC loop, and the complementary Van der Waals attraction. Our methods demonstrate encouraging results by yielding conformationally stable and high-potential CP binders that should have potential applicability in future CP drug development.Communicated by Ramaswamy H. Sarma.


A high-throughput MD screening (HTMDS) process for cyclic peptides (CPs) binders designed with canonical and non-canonical amino acids.698,800 CP candidates with a total of 25,570 ns MD simulations were performed to study the protein-ligand binding interactions and CP design.Some potent CP candidates were obtained with high binding free energies (ΔGbind) estimated by the MM/PBSA approach compared with the standard inhibitor C-38 against the bromodomain (BrD) of ATAD2B.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos Cíclicos , Peptídeos Cíclicos/farmacologia , Sítios de Ligação , Conformação Molecular , Hidrogênio , Simulação de Acoplamento Molecular
11.
BMC Immunol ; 24(1): 50, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057716

RESUMO

PURPOSE: Screening of lysosome-related genes in sepsis patients to provide direction for lysosome-targeted therapy. METHODS: Peripheral blood samples were obtained from 22 patients diagnosed with sepsis and 10 normal controls for the purpose of RNA sequencing and subsequent analysis of differential gene expression. Concurrently, lysosome-related genes were acquired from the Gene Ontology database. The intersecting genes between the differential genes and lysosome-related genes were then subjected to PPI, GO and KEGG analyses. Core genes were identified through survival analysis, and their expression trends in different groups were determined using meta-analysis. Single-cell RNA sequencing was used to clarify the cellular localization of core genes. RESULTS: The intersection of 1328 sepsis-differential genes with 878 lysosome-related genes yielded 76 genes. PPI analysis showed that intersecting genes were mainly involved in Cellular process, Response to stimulus, Immune system process, Signal transduction, Lysosome. GO and KEGG analysis showed that intersecting genes were mainly involved in leukocyte mediated immunity, cell activation involved in immune response, lytic vacuole, lysosome. Survival analysis screened four genes positively correlated with sepsis prognosis, namely GNLY, GZMB, PRF1 and RASGRP1. The meta-analysis revealed that the expression levels of these four genes were significantly higher in the normal control group compared to the sepsis group, which aligns with the findings from RNA sequencing data. Furthermore, single-cell RNA sequencing demonstrated that T cells and NK cells exhibited high expression levels of GNLY, GZMB, PRF1, and RASGRP1. CONCLUSION: GNLY, GZMB, PRF1, and RASGRP1, which are lysosome-related genes, are closely linked to the prognosis of sepsis and could potentially serve as novel research targets for sepsis, offering valuable insights for the development of lysosome-targeted therapy. The clinical trial registration number is ChiCTR1900021261, and the registration date is February 4, 2019.


Assuntos
Lisossomos , Sepse , Humanos , Ontologia Genética , Fatores de Troca do Nucleotídeo Guanina , Lisossomos/genética , Sepse/genética , Análise de Sequência de RNA , Prognóstico
12.
Front Plant Sci ; 14: 1246717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915513

RESUMO

Introduction: The accurate extraction of navigation paths is crucial for the automated navigation of agricultural robots. Navigation line extraction in complex environments such as Panax notoginseng shade house can be challenging due to factors including similar colors between the fork rows and soil, and the shadows cast by shade nets. Methods: In this paper, we propose a new method for navigation line extraction based on deep learning and least squares (DL-LS) algorithms. We improve the YOLOv5s algorithm by introducing MobileNetv3 and ECANet. The trained model detects the seven-fork roots in the effective area between rows and uses the root point substitution method to determine the coordinates of the localization base points of the seven-fork root points. The seven-fork column lines on both sides of the plant monopoly are fitted using the least squares method. Results: The experimental results indicate that Im-YOLOv5s achieves higher detection performance than other detection models. Through these improvements, Im-YOLOv5s achieves a mAP (mean Average Precision) of 94.9%. Compared to YOLOv5s, Im-YOLOv5s improves the average accuracy and frame rate by 1.9% and 27.7%, respectively, and the weight size is reduced by 47.9%. The results also reveal the ability of DL-LS to accurately extract seven-fork row lines, with a maximum deviation of the navigation baseline row direction of 1.64°, meeting the requirements of robot navigation line extraction. Discussion: The results shows that compared to existing models, this model is more effective in detecting the seven-fork roots in images, and the computational complexity of the model is smaller. Our proposed method provides a basis for the intelligent mechanization of Panax notoginseng planting.

13.
Elife ; 122023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991825

RESUMO

The role of regulated cell death in organ development, particularly the impact of non-apoptotic cell death, remains largely uncharted. Ferroptosis, a non-apoptotic cell death pathway known for its iron dependence and lethal lipid peroxidation, is currently being rigorously investigated for its pathological functions. The balance between ferroptotic stress (iron and iron-dependent lipid peroxidation) and ferroptosis supervising pathways (anti-lipid peroxidation systems) serves as the key mechanism regulating the activation of ferroptosis. Compared with other forms of regulated necrotic cell death, ferroptosis is critically related to the metabolism of lipid and iron which are also important in organ development. In our study, we examined the role of ferroptosis in organogenesis using an ex vivo tooth germ culture model, investigating the presence and impact of ferroptotic stress on tooth germ development. Our findings revealed that ferroptotic stress increased during tooth development, while the expression of glutathione peroxidase 4 (Gpx4), a crucial anti-lipid peroxidation enzyme, also escalated in dental epithelium/mesenchyme cells. The inhibition of ferroptosis was found to partially rescue erastin-impaired tooth morphogenesis. Our results suggest that while ferroptotic stress is present during tooth organogenesis, its effects are efficaciously controlled by the subsequent upregulation of Gpx4. Notably, an overabundance of ferroptotic stress, as induced by erastin, suppresses tooth morphogenesis.


Assuntos
Ferroptose , Odontogênese , Organogênese , Peroxidação de Lipídeos , Ferro
14.
Nano Lett ; 23(23): 11184-11192, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38029280

RESUMO

Facing the defects and energy barrier at the interface of perovskite solar cells, we propose a chiral molecule engineering strategy to simultaneously heal interfacial defects and regulate interfacial energy band alignment. S-ibuprofen (S-IBU), R-ibuprofen (R-IBU), and racemic ibuprofen (rac-IBU) are used to post-treat perovskite films. rac-IBU molecules possess the strongest anchoring on the surface of perovskites among all chiral molecules, translating into the best defect passivation effect. The hydrophobic isobutyl group and benzene ring could increase the film moisture resistance ability. Due to reduced interfacial defects and interfacial energy barrier, rac-IBU enables efficient devices with a maximum efficiency exceeding 24% based on vacuum flash technology without antisolvents. The encapsulated rac-IBU-modified device could maintain 90% of its initial performance after 1040 h of continuous maximum power point tracking. This work provides a feasible route to minimize interfacial nonradiative recombination losses by controlling spatial conformation via rational chiral molecule engineering.

15.
ACS Appl Mater Interfaces ; 15(39): 46236-46246, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37729386

RESUMO

Combining MoS2 with mature silicon technology is an effective method for preparing high-performance photodetectors. However, the previously studied MoS2/silicon-based heterojunction photodetectors cannot simultaneously demonstrate high responsivity, a fast response time, and broad spectral detection. We constructed a broad spectral n-type MoS2/p-type silicon-based heterojunction photodetector. The SiO2 dielectric layer on the silicon substrate was pretreated with soft plasma to change its thickness and surface state. The pretreated SiO2 dielectric layer and the silicon substrate constitute a multilayer heterostructure with a high carrier concentration and responsiveness. Taking silicon-based and n-type MoS2 heterojunction photodetectors as examples, its responsivity can reach 4.05 × 104 A W1- at 637 nm wavelength with a power density of 2 µW mm-2, and the detectable spectral range is measured from 447 to 1600 nm. This pretreated substrate was proven applicable to other n-type TMDCs, such as MoTe2, ReS2, etc., with certain versatility.

16.
Nanotechnology ; 34(50)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37748477

RESUMO

Two-dimensional (2D) p-n heterojunctions have attracted great attention due to their outstanding properties in electronic and optoelectronic devices, especially in photodetectors. Various types of heterojunctions have been constituted by mechanical exfoliation and stacking. However, achieving controlled growth of heterojunction structures remains a tremendous challenge. Here, we employed a two-step KI-assisted confined-space chemical vapor deposition method to prepare multilayer WSe2/SnS2p-n heterojunctions. Optical characterization results revealed that the prepared WSe2/SnS2vertical heterostructures have clear interfaces as well as vertical heterostructures. The electrical and optoelectronic properties were investigated by constructing the corresponding heterojunction devices, which exhibited good rectification characteristics and obtained a high detectivity of 7.85 × 1012Jones and a photoresponse of 227.3 A W-1under visible light irradiation, as well as a fast rise/fall time of 166/440µs. These remarkable performances are likely attributed to the ultra-low dark current generated in the depletion region at the junction and the high direct tunneling current during illumination. This work demonstrates the value of multilayer WSe2/SnS2heterojunctions for applications in high-performance photodetectors.

17.
Zhongguo Gu Shang ; 36(8): 777-81, 2023 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-37605919

RESUMO

OBJECTIVE: To explore clinical effect of repairing anterior talofibular ligament with knot-free anchors under total ankle arthroscopy in treating chronic lateral ankle instability. METHODS: From April 2018 to August 2021, 24 patients with chronic lateral ankle instability were treated with knot-free anchors under total ankle arthroscopy to repair anterior talofibular ligament, including 16 males and 8 females, aged from 22 to 42 years old with an average of(28.6±5.8) years old;the time from injury to opertaion ranged from 6 to 10 months with an average of(7.7±1.3) months. Preoperative and postoperative American Orhopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS), talar tilt, anterior talar translation(ATT) were recorded and compared. RESULTS: All patients were followed up from 10 to 12 months with an average of (10.2±1.14) months. Incision were healed at stageⅠ, and no infection, nerve injury and lateral ankle instability occurred. AOFAS score improved from(52.79±8.96) before opertaion to (93.00± 4.01) at 6 months after operation, 23 patients got excellent result and 1 good;VAS decreased from (5.50±0.98) before opertaion to (1.04±0.80) at 6 months after operation(P<0.05);talar tilt decreased from(9.16±2.09)° to (3.10±1.72)° at 3 months after operation(P<0.05);ATT decreased from(8.80±2.55) mm to (2.98±1.97) mm at 3 months after operation(P<0.05). Twenty-four patients drawer test and varus-valgus rotation wer negative. CONCLUSION: Repairing anterior talofibular ligament with knot-free anchors under total ankle arthroscopy for the treatment of chronic lateral ankle instability has advantages of less trauma, less complications safe and reliable, and good recovery of ankle joint function.


Assuntos
Instabilidade Articular , Ligamentos Laterais do Tornozelo , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Articulação do Tornozelo/cirurgia , Tornozelo , Artroscopia , Ligamentos Laterais do Tornozelo/cirurgia , Instabilidade Articular/cirurgia
18.
Aging Cell ; 22(9): e13913, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37340571

RESUMO

Hippo-independent YAP dysfunction has been demonstrated to cause chronological aging of stromal cells by impairing the integrity of nuclear envelope (NE). In parallel with this report, we uncover that YAP activity also controls another type of cellular senescence, the replicative senescence in in vitro expansion of mesenchymal stromal cells (MSCs), but this event is Hippo phosphorylation-dependent, and there exist another NE integrity-independent downstream mechanisms of YAP. Specifically, Hippo phosphorylation causes reduced nuclear/active YAP and then decreases the level of YAP protein in the proceeding of replicative senescence. YAP/TEAD governs RRM2 expression to release replicative toxicity (RT) via licensing G1/S transition. Besides, YAP controls the core transcriptomics of RT to delay the onset of genome instability and enhances DNA damage response/repair. Hippo-off mutations of YAP (YAPS127A/S381A ) satisfactorily release RT via maintaining cell cycle and reducing genome instability, finally rejuvenating MSCs and restoring their regenerative capabilities without risks of tumorigenesis.


Assuntos
Células-Tronco Mesenquimais , Proteínas de Sinalização YAP , Humanos , Proteínas de Ciclo Celular/genética , Instabilidade Genômica , Fosforilação
19.
ACS Appl Mater Interfaces ; 15(26): 31243-31255, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37350582

RESUMO

Increased intracranial pressure after traumatic brain injury (TBI) is an urgent problem in clinical practice. A pliable hydrogel is preferred for cranioplasty applications after TBI since it can protect brain tissue and promote bone healing. Nevertheless, biohydrogels for cranial bone regeneration still face challenges of poor mechanical properties, large swelling ratios, and low osteogenesis activity. Herein, inspired by Hofmeister effects, biopolymer hydrogels composed of protein and polysaccharides were treated with a Hofmeister series including a series of monovalent and divalent anions. Our results reveal that the divalent anion-cross-linked biohydrogels exhibit stronger mechanical properties and lower swelling ratios compared with monovalent-anion treated gels. Intriguingly, the divalent HPO42- anion induced biohybrid hydrogels with excellent mechanical behaviors (3.7 ± 0.58 MPa, 484 ± 76.7 kPa, and 148.3 ± 6.85 kJ/m3), anti-swelling capability (16.7%), and gradual degradation ability, significantly stimulating osteogenic differentiation and in vivo cranial bone regeneration. Overall, this study may provide new insights into the design of biomimetic hydrogels for treating cranial bone defects after TBI.


Assuntos
Regeneração Óssea , Osteogênese , Crânio , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Encéfalo
20.
Adv Mater ; 35(23): e2301028, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37026996

RESUMO

Interfacial nonradiative recombination loss is a huge barrier to advance the photovoltaic performance. Here, one effective interfacial defect and carrier dynamics management strategy by synergistic modulation of functional groups and spatial conformation of ammonium salt molecules is proposed. The surface treatment with 3-ammonium propionic acid iodide (3-APAI) does not form 2D perovskite passivation layer while the propylammonium ions and 5-aminopentanoic acid hydroiodide post-treatment lead to the formation of 2D perovskite passivation layers. Due to appropriate alkyl chain length, theoretical and experimental results manifest that COOH and NH3 + groups in 3-APAI molecules can form coordination bonding with undercoordinated Pb2+ and ionic bonding and hydrogen bonding with octahedron PbI6 4- , respectively, which makes both groups be simultaneously firmly anchored on the surface of perovskite films. This will strengthen defect passivation effect and improve interfacial carrier transport and transfer. The synergistic effect of functional groups and spatial conformation confers 3-APAI better defect passivation effect than 2D perovskite layers. The 3-APAI-modified device based on vacuum flash technology achieves an alluring peak efficiency of 24.72% (certified 23.68%), which is among highly efficient devices fabricated without antisolvents. Furthermore, the encapsulated 3-APAI-modified device degrades by less than 4% after 1400 h of continuous one sun illumination.

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