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1.
Cell ; 171(4): 849-864.e25, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100074

RESUMO

Angiogenin (ANG) is a secreted ribonuclease (RNase) with cell-type- and context-specific roles in growth, survival, and regeneration. Although these functions require receptor-mediated endocytosis and appropriate subcellular localization, the identity of the cell surface receptor remains undefined. Here, we show that plexin-B2 (PLXNB2) is the functional receptor for ANG in endothelial, cancer, neuronal, and normal hematopoietic and leukemic stem and progenitor cells. Mechanistically, PLXNB2 mediates intracellular RNA processing that contribute to cell growth, survival, and regenerative capabilities of ANG. Antibodies generated against the ANG-binding site on PLXNB2 restricts ANG activity in vitro and in vivo, resulting in inhibition of established xenograft tumors, ANG-induced neurogenesis and neuroprotection, levels of pro-self-renewal transcripts in hematopoietic and patient-derived leukemic stem and progenitor cells, and reduced progression of leukemia in vivo. PLXNB2 is therefore required for the physiological and pathological functions of ANG and has significant therapeutic potential in solid and hematopoietic cancers and neurodegenerative diseases.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Células-Tronco Hematopoéticas/metabolismo , Xenoenxertos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurogênese , Ribonuclease Pancreático/química
2.
Cell ; 166(4): 894-906, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27518564

RESUMO

Regulation of stem and progenitor cell populations is critical in the development, maintenance, and regeneration of tissues. Here, we define a novel mechanism by which a niche-secreted RNase, angiogenin (ANG), distinctively alters the functional characteristics of primitive hematopoietic stem/progenitor cells (HSPCs) compared with lineage-committed myeloid-restricted progenitor (MyePro) cells. Specifically, ANG reduces the proliferative capacity of HSPC while simultaneously increasing proliferation of MyePro cells. Mechanistically, ANG induces cell-type-specific RNA-processing events: tRNA-derived stress-induced small RNA (tiRNA) generation in HSPCs and rRNA induction in MyePro cells, leading to respective reduction and increase in protein synthesis. Recombinant ANG protein improves survival of irradiated animals and enhances hematopoietic regeneration of mouse and human HSPCs in transplantation. Thus, ANG plays a non-cell-autonomous role in regulation of hematopoiesis by simultaneously preserving HSPC stemness and promoting MyePro proliferation. These cell-type-specific functions of ANG suggest considerable therapeutic potential.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Proliferação de Células , Hematopoese , Células-Tronco Hematopoéticas/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , RNA de Transferência/metabolismo , RNA não Traduzido/metabolismo
3.
N Engl J Med ; 390(20): 1862-1872, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38752650

RESUMO

BACKGROUND: Treatment of acute stroke, before a distinction can be made between ischemic and hemorrhagic types, is challenging. Whether very early blood-pressure control in the ambulance improves outcomes among patients with undifferentiated acute stroke is uncertain. METHODS: We randomly assigned patients with suspected acute stroke that caused a motor deficit and with elevated systolic blood pressure (≥150 mm Hg), who were assessed in the ambulance within 2 hours after the onset of symptoms, to receive immediate treatment to lower the systolic blood pressure (target range, 130 to 140 mm Hg) (intervention group) or usual blood-pressure management (usual-care group). The primary efficacy outcome was functional status as assessed by the score on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) at 90 days after randomization. The primary safety outcome was any serious adverse event. RESULTS: A total of 2404 patients (mean age, 70 years) in China underwent randomization and provided consent for the trial: 1205 in the intervention group and 1199 in the usual-care group. The median time between symptom onset and randomization was 61 minutes (interquartile range, 41 to 93), and the mean blood pressure at randomization was 178/98 mm Hg. Stroke was subsequently confirmed by imaging in 2240 patients, of whom 1041 (46.5%) had a hemorrhagic stroke. At the time of patients' arrival at the hospital, the mean systolic blood pressure in the intervention group was 159 mm Hg, as compared with 170 mm Hg in the usual-care group. Overall, there was no difference in functional outcome between the two groups (common odds ratio, 1.00; 95% confidence interval [CI], 0.87 to 1.15), and the incidence of serious adverse events was similar in the two groups. Prehospital reduction of blood pressure was associated with a decrease in the odds of a poor functional outcome among patients with hemorrhagic stroke (common odds ratio, 0.75; 95% CI, 0.60 to 0.92) but an increase among patients with cerebral ischemia (common odds ratio, 1.30; 95% CI, 1.06 to 1.60). CONCLUSIONS: In this trial, prehospital blood-pressure reduction did not improve functional outcomes in a cohort of patients with undifferentiated acute stroke, of whom 46.5% subsequently received a diagnosis of hemorrhagic stroke. (Funded by the National Health and Medical Research Council of Australia and others; INTERACT4 ClinicalTrials.gov number, NCT03790800; Chinese Trial Registry number, ChiCTR1900020534.).


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Serviços Médicos de Emergência , Hipertensão , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ambulâncias , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , AVC Isquêmico/terapia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Tempo para o Tratamento , Doença Aguda , Estado Funcional , China
4.
Mol Genet Genomics ; 299(1): 50, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734849

RESUMO

Intracerebral hemorrhage (ICH) is one of the major causes of death and disability, and hypertensive ICH (HICH) is the most common type of ICH. Currently, the outcomes of HICH patients remain poor after treatment, and early prognosis prediction of HICH is important. However, there are limited effective clinical treatments and biomarkers for HICH patients. Although circRNA has been widely studied in diseases, the role of plasma exosomal circRNAs in HICH remains unknown. The present study was conducted to investigate the characteristics and function of plasma exosomal circRNAs in six HICH patients using circRNA microarray and bioinformatics analysis. The results showed that there were 499 differentially expressed exosomal circRNAs between the HICH patients and control subjects. According to GO annotation and KEGG pathway analyses, the targets regulated by differentially expressed exosomal circRNAs were tightly related to the development of HICH via nerve/neuronal growth, neuroinflammation and endothelial homeostasis. And the differentially expressed exosomal circRNAs could mainly bind to four RNA-binding proteins (EIF4A3, FMRP, AGO2 and HUR). Moreover, of differentially expressed exosomal circRNAs, hsa_circ_00054843, hsa_circ_0010493 and hsa_circ_00090516 were significantly associated with bleeding volume and Glasgow Coma Scale score of the subjects. Our findings firstly revealed that the plasma exosomal circRNAs are significantly involved in the progression of HICH, and could be potent biomarkers for HICH. This provides the basis for further research to pinpoint the best biomarkers and illustrate the mechanism of exosomal circRNAs in HICH.


Assuntos
Exossomos , RNA Circular , Humanos , RNA Circular/genética , RNA Circular/sangue , Exossomos/genética , Exossomos/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Hemorragia Intracraniana Hipertensiva/genética , Hemorragia Intracraniana Hipertensiva/sangue , Biomarcadores/sangue , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Hemorragia Cerebral/genética , Hemorragia Cerebral/sangue , Redes Reguladoras de Genes
5.
Cell Mol Life Sci ; 80(6): 154, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204469

RESUMO

Inflammation can impair intestinal barrier, while increased epithelial permeability can lead to inflammation. In this study, we found that the expression of Tspan8, a tetraspanin expressed specifically in epithelial cells, is downregulated in mouse model of ulcerative disease (UC) but correlated with those of cell-cell junction components, such as claudins and E-cadherin, suggesting that Tspan8 supports intestinal epithelial barrier. Tspan8 removal increases intestinal epithelial permeability and upregulates IFN-γ-Stat1 signaling. We also demonstrated that Tspan8 coalesces with lipid rafts and facilitates IFNγ-R1 localization at or near lipid rafts. As IFN-γ induces its receptor undergoing clathrin- or lipid raft-dependent endocytosis and IFN-γR endocytosis plays an important role in Jak-Stat1 signaling, our analysis on IFN-γR endocytosis revealed that Tspan8 silencing impairs lipid raft-mediated but promotes clathrin-mediated endocytosis of IFN-γR1, leading to increased Stat1 signaling. These changes in IFN-γR1 endocytosis upon Tspan8 silencing correlates with fewer lipid raft component GM1 at the cell surface and more clathrin heavy chain in the cells. Our findings indicate that Tspan8 determines the IFN-γR1 endocytosis route, to restrain Stat1 signaling, stabilize intestine epithelium, and subsequently prevent intestine from inflammation. Our finding also implies that Tspan8 is needed for proper endocytosis through lipid rafts.


Assuntos
Mucosa Intestinal , Receptores de Interferon , Tetraspaninas , Animais , Camundongos , Clatrina/metabolismo , Endocitose/fisiologia , Inflamação/metabolismo , Interferons/metabolismo , Mucosa Intestinal/metabolismo , Receptores de Interferon/metabolismo , Tetraspaninas/genética , Tetraspaninas/metabolismo
6.
Sensors (Basel) ; 24(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732773

RESUMO

Surface defect detection of strip steel is an important guarantee for improving the production quality of strip steel. However, due to the diverse types, scales, and texture structures of surface defects on strip steel, as well as the irregular distribution of defects, it is difficult to achieve rapid and accurate detection of strip steel surface defects with existing methods. This article proposes a real-time and high-precision surface defect detection algorithm for strip steel based on YOLOv7. Firstly, Partial Conv is used to replace the conventional convolution blocks of the backbone network to reduce the size of the network model and improve the speed of detection; Secondly, The CA attention mechanism module is added to the ELAN module to enhance the ability of the network to extract detect features and improve the effectiveness of detect detection in complex environments; Finally, The SPD convolution module is introduced at the output end to improve the detection performance of small targets with surface defects on steel. The experimental results on the NEU-DET dataset indicate that the mean average accuracy (mAP@IoU = 0.5) is 80.4%, which is 4.0% higher than the baseline network. The number of parameters is reduced by 8.9%, and the computational load is reduced by 21.9% (GFLOPs). The detection speed reaches 90.9 FPS, which can well meet the requirements of real-time detection.

7.
Water Sci Technol ; 89(11): 3021-3034, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877628

RESUMO

Drainage modeling that accurately captures urban storm inundation serves as the foundation for flood warning and drainage scheduling. In this paper, we proposed a novel coupling ideology that, by integrating 2D-1D and 1D-2D unidirectional processes, overcomes the drawback of the conventional unidirectional coupling approach that fails to properly represent the rainfall surface catchment dynamics, and provides more coherent hydrological implications compared to the bidirectional coupling concept. This paper first referred to a laboratory experimental case from the literature, applied and analyzed the coupling scheme proposed in this paper and the bidirectional coupling scheme that has been widely studied in recent years, compared the two coupling solutions in terms of the resulting accuracy and applicability, and discussed their respective strengths and weaknesses to validate the reliability of the proposed method. The verified proposed coupling scheme was then applied to the modeling of a real drainage system in a region of Nanjing, China, and the results proved that the coupling mechanism proposed in this study is of practical application value.


Assuntos
Cidades , Inundações , Hidrodinâmica , Modelos Teóricos , China , Esgotos , Drenagem Sanitária
8.
Emerg Infect Dis ; 29(7): 1425-1428, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37347816

RESUMO

Candida vulturna belongs to the Candida haemulonii species complex and is phylogenetically related to C. auris. We report a C. vulturna outbreak among persons in Shanxi Province, China, during 2019-2022. Isolates were resistant to multiple antifungal drugs and exhibited enhanced adhesion and biofilm formation properties.


Assuntos
Candida , Candidíase , Candidíase/epidemiologia , Candidíase/microbiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , China/epidemiologia , Testes de Sensibilidade Microbiana
9.
J Transl Med ; 21(1): 109, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765396

RESUMO

BACKGROUND: Inadequate immunity caused by poor immune surveillance leads to tumorigenesis, while excessive immunity due to breakdown of immune tolerance causes autoimmune genesis. Although the function of immunity during the onset of these two processes appears to be distinct, the underlying mechanism is shared. To date, gene expression data for large bodies of clinical samples are available, but the resemblances of tumorigenesis and autoimmune genesis in terms of immune responses remains to be summed up. METHODS: Considering the high disease prevalence, we chose invasive ductal carcinoma (IDC) and systemic lupus erythematosus (SLE) to study the potential commonalities of immune responses. We obtained gene expression data of IDC/SLE patients and normal controls from five IDC databases (GSE29044, GSE21422, GSE22840, GSE15852, and GSE9309) and five SLE databases (GSE154851, GSE99967, GSE61635, GSE50635, and GSE17755). We intended to identify genes differentially expressed in both IDC and SLE by using three bioinformatics tools including GEO2R, the limma R package, and Weighted Gene Co-expression Network Analysis (WGCNA) to perform function enrichment, protein-protein network, and signaling pathway analyses. RESULTS: The mRNA levels of signal transducer and activator of transcription 1 (STAT1), 2'-5'-oligoadenylate synthetase 1 (OAS1), 2'-5'-oligoadenylate synthetase like (OASL), and PML nuclear body scaffold (PML) were found to be differentially expressed in both IDC and SLE by using three different bioinformatics tools of GEO2R, the limma R package and WGCNA. From the combined databases in this study, the mRNA levels of STAT1 and OAS1 were increased in IDC while reduced in SLE. And the mRNA levels of OASL and PML were elevated in both IDC and SLE. Based on Kyoto Encyclopedia of Genes and Genomes pathway analysis and QIAGEN Ingenuity Pathway Analysis, both IDC and SLE were correlated with the changes of multiple components involved in the Interferon (IFN)-Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway. CONCLUSION: The expression levels of STAT1 and OAS1 manifest the opposite expression tendency across cancer and autoimmune disease. They are components in the IFN-JAK-STAT signaling pathway related to both tumorigenesis and autoimmune genesis. STAT1 and OAS1-associated IFN-JAK-STAT signaling could explain the commonalities during tumorigenesis and autoimmune genesis and render significant information for more precise treatment from the point of immune homeostasis.


Assuntos
Lúpus Eritematoso Sistêmico , Neoplasias , Humanos , Lúpus Eritematoso Sistêmico/genética , Janus Quinases/uso terapêutico , Carcinogênese , Biologia Computacional , RNA Mensageiro/metabolismo
10.
Cell Immunol ; 388-389: 104730, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37210768

RESUMO

HHLA2 has been recently demonstrated to play multifaceted roles in several types of cancers. However, its underlying mechanism in the progression of human ovarian cancer (OC) remains largely unexplored. In the present study, we aimed to determine whether downregulation of HHLA2 inhibited malignant phenotypes of human OC cells and explore its specific mechanism. Our results revealed that downregulation of HHLA2 by transfection with a lentiviral vector significantly suppressed the viability, invasion, and migration of OC cells. Interaction study showed that downregulation of HHLA2 in OC cells reduced the expression of CA9 and increased the expressions of p-IKKß and p-RelA. Conversely, the viability, invasion, and migration of HHLA2-depleted OC cells were increased when CA9 was upregulated. In vivo, we found that downregulation of HHLA2 significantly inhibited tumor growth, which was reversed by CA9 overexpression. In addition, downregulation of HHLA2 inhibited the OC progression via activating the NF-κB signaling pathway and decreasing the expression of CA9. Collectively, our data suggested a link between HHLA2 and NF-κB axis in the pathogenesis of OC, and these findings might provide valuable insights into the development of novel potential therapeutic targets for OC.


Assuntos
NF-kappa B , Neoplasias Ovarianas , Humanos , Feminino , NF-kappa B/metabolismo , Regulação para Baixo , Linhagem Celular Tumoral , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Transdução de Sinais , Movimento Celular , Proliferação de Células , Anidrase Carbônica IX/genética , Anidrase Carbônica IX/metabolismo , Antígenos de Neoplasias , Imunoglobulinas/metabolismo
11.
Nano Lett ; 22(6): 2429-2436, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35285233

RESUMO

Lithium cobalt oxide (LCO) is a widely used cathode material for lithium-ion batteries. However, it suffers from irreversible phase transition during cycling because of high cutoff voltage or huge concentration polarization in thick electrode, resulting in deteriorated cyclability. Here, we design a low tortuous LiCoO2 (LCO-LT) electrode by ice-templating method and investigate the reversibility of LCO phase transition. LCO-LT thick electrode shows accelerated lithium-ion transport and reduced concentration polarization, achieving excellent rate capability and homogeneous actual operating voltage. Moreover, LCO-LT thick electrode exhibits a durable phase transition between O2 and H1-3, mitigated volume expansion, and suppressed microcrack formation. LCO-LT electrode (25 mg cm-2) delivers improved capacity retentions of 94.4% after 200 cycles and 93.3% after 150 cycles at cutoff voltages of 4.3 and 4.5 V, respectively. This strategy provides a new concept to improve the reversibility of LCO phase transition in thick electrode by low tortuosity design.

12.
J Environ Manage ; 335: 117579, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36854235

RESUMO

The construction of an efficient monitoring network is critical for the effective and safe management of urban drainage systems. This study developed a re-clustering methodology that incorporates additional perspectives beyond node similarity to improve the traditional clustering process for optimal sensor placement. Instead of targeting event-specific water quality or hydraulic monitoring, the method integrates the water hydraulic and quality characteristics of nodes in response to the demand for routine monitoring. The implementation of this method first applies model simulation to generate the attribute datasets required for clustering analysis, and then re-clusters the initial clustering result according to the constructed re-clustering potential indices. And the information theory-based evaluation metrics were introduced to quantitatively assess the sensor deployment scheme obtained by amalgamating the two clustering results. Two networks with different drainage systems and sizes were chosen as case studies to illustrate the application of the framework. The results demonstrate that the clustering process enables to expand the information contained in the monitoring network, and that the re-clustering strategy can generate more comprehensive and practical solutions upon this basis.


Assuntos
Qualidade da Água , Simulação por Computador , Análise por Conglomerados
13.
Br J Cancer ; 127(8): 1525-1533, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35974099

RESUMO

INTRODUCTION: The NHS Bowel Cancer Screening Programme (BCSP) faces endoscopy capacity challenges from the COVID-19 pandemic and plans to lower the screening starting age. This may necessitate modifying the interscreening interval or threshold. METHODS: We analysed data from the English Faecal Immunochemical Testing (FIT) pilot, comprising 27,238 individuals aged 59-75, screened for colorectal cancer (CRC) using FIT. We estimated screening sensitivity to CRC, adenomas, advanced adenomas (AA) and mean sojourn time of each pathology by faecal haemoglobin (f-Hb) thresholds, then predicted the detection of these abnormalities by interscreening interval and f-Hb threshold. RESULTS: Current 2-yearly screening with a f-Hb threshold of 120 µg/g was estimated to generate 16,092 colonoscopies, prevent 186 CRCs, detect 1142 CRCs, 7086 adenomas and 4259 AAs per 100,000 screened over 15 years. A higher threshold at 180 µg/g would reduce required colonoscopies to 11,500, prevent 131 CRCs, detect 1077 CRCs, 4961 adenomas and 3184 AAs. A longer interscreening interval of 3 years would reduce required colonoscopies to 10,283, prevent 126 and detect 909 CRCs, 4796 adenomas and 2986 AAs. CONCLUSION: Increasing the f-Hb threshold was estimated to be more efficient than increasing the interscreening interval regarding overall colonoscopies per screen-benefited cancer. Increasing the interval was more efficient regarding colonoscopies per cancer prevented.


Assuntos
Adenoma , COVID-19 , Neoplasias Colorretais , Adenoma/diagnóstico , Adenoma/epidemiologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer/métodos , Inglaterra , Hemoglobinas/análise , Humanos , Pandemias , Projetos Piloto
14.
Br J Cancer ; 127(3): 422-435, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35418212

RESUMO

BACKGROUND: Angiogenin is a multifunctional secreted ribonuclease that is upregulated in human cancers and downregulated or mutationally inactivated in neurodegenerative diseases. A role for angiogenin in glioblastoma was inferred from the inverse correlation of angiogenin expression with patient survival but had not been experimentally investigated. METHODS: Angiogenin knockout mice were generated and the effect of angiogenin deficiency on glioblastoma progression was examined. Angiogenin and plexin-B2 genes were knocked down in glioblastoma cells and the changes in cell proliferation, invasion and vascular association were examined. Monoclonal antibodies of angiogenin and small molecules were used to assess the therapeutic activity of the angiogenin-plexin-B2 pathway in both genetic and xenograft animal models. RESULTS: Deletion of Ang1 gene prolonged survival of PDGF-induced glioblastoma in mice in the Ink4a/Arf-/-:Pten-/- background, accompanied by decreased invasion, vascular association and proliferation. Angiogenin upregulated MMP9 and CD24 leading to enhanced invasion and vascular association. Inhibition of angiogenin or plexin-B2, either by shRNA, monoclonal antibody or small molecule inhibitor, decreases sphere formation of patient-derived glioma stem cells, reduces glioblastoma proliferation and invasion and inhibits glioblastoma growth in both genetic and xenograft animal models. CONCLUSIONS: Angiogenin and its receptor, plexin-B2, are a pair of novel regulators that mediate invasion, vascular association and proliferation of glioblastoma cells. Inhibitors of the angiogenin-plexin-B2 axis have therapeutic potential against glioblastoma.


Assuntos
Glioblastoma , Proteínas do Tecido Nervoso , Ribonuclease Pancreático , Animais , Linhagem Celular Tumoral , Proliferação de Células , Glioblastoma/tratamento farmacológico , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo
15.
Small ; 18(22): e2200563, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35289505

RESUMO

Solar-blind photodetectors (PDs) are widely applicable in special, military, medical, environmental, and commercial fields. However, high performance and flexible PD for deep ultraviolet (UV) range is still a challenge. Here, it is demonstrated that an upconversion of photon absorption beyond the energy bandgap is achieved in the ZnO nanoarray/h-BN heterostructure, which enables the ultrahigh responsivity of a solar-blind photodetecting paper. The direct growth of ultralong ZnO nanoarray on polycrystalline copper paper induced by h-BN 2D interlayer is obtained. Meanwhile, strong photon trapping takes place within the ZnO nanoarray forest through the cyclic state transition of surface oxygen ions, resulting in an extremely high absorption efficiency (> 99.5%). A flexible photodetecting paper is fabricated for switchable detections between near UV and deep UV signals by critical external bias. The device shows robust reliability, ultrahigh responsivity up to 700 A W-1 @ 265-276 nm, and high photoconductive gain of ≈2 × 103 . A negative differential resistance effect is revealed for driving the rapid transfer of up-converted electrons between adjacent energy valleys (Γ to A) above the critical bias (3.9 V). The discovered rationale and device structure are expected to bring high-efficiency deep UV detecting and future wearable applications.


Assuntos
Óxido de Zinco , Fótons , Reprodutibilidade dos Testes , Luz Solar , Raios Ultravioleta , Óxido de Zinco/química
16.
Opt Express ; 30(5): 6700-6712, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299449

RESUMO

Magneto-optical (MO) properties of the bilayed Au/BIG and trilayered Au/BIG/Au magneto-plasmonic crystals (MPCs) were analyzed by the finite-difference time-domain method. In contrast to the low deflection angle and transmission of the smooth thin film, all the heterostructures with perforated holes in the top Au film displayed a similar trend with two strong resonant bands in Faraday rotation and transmittance in the near infrared wavelength range. The bands and electric distribution relative to the component and hole structure were revealed. The MPC with plasmonic hexagonal holes was found to own superior Faraday effects with distinctive anisotropy. The evolution of the resonant bands with the size and period of hexagonal holes, the thickness of different layers, and the incident light polarization was illustrated. The Faraday rotation of the optimized bilayed and trilayered hexagonal MPCs was improved 15.3 and 17.5 times, and the transmittance was enhanced 12.1 and 11.1 folds respectively at the resonant wavelength in comparison to the continuous Au/BIG film, indicating that the systems might find potential application in MO devices.

17.
Phys Chem Chem Phys ; 24(9): 5529-5538, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35172325

RESUMO

Quantum states and arrangement of valence levels determine most of the electronic and optical properties of semiconductors. Since the crystal field split-off hole (CH) band is the top valence band in high-Al-content AlGaN, TM-polarized optical anisotropy has become the limiting factor for efficient deep-ultraviolet (DUV) light emission. Additional potentials, including on-site Coulomb interaction and orbital state coupling induced by magnesium (Mg) doping, are proposed in this work to regulate the valence level arrangement of AlN/Al0.75Ga0.25N quantum wells (QWs). Diverse responses of valence quantum states |pi〉 (i = x, y, or z) of AlGaN to additional potentials due to different configurations and interactions of orbitals revealed by first-principles simulations are understood in terms of the linear combination of atomic orbital states. A positive charge and large Mg dopant in QWs introduce an additional Coulomb potential and modulate the orbital coupling distance. For the CH band (pz orbital), the Mg-induced Coulomb potential compensates the orbital coupling energy. Meanwhile, the heavy/light hole (HH/LH) bands (px and py orbitals) are elevated by the Mg-induced Coulomb potential. Consequently, HH/LH energy levels are relatively shifted upward and replace the CH level to be the top of the valence band. The inversion of optical anisotropy and enhancement of TE-polarized emission are further confirmed experimentally via spectroscopic ellipsometry.

18.
J Sep Sci ; 45(13): 2148-2160, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35404530

RESUMO

The Shabyar tablet is commonly used as a traditional ethnic medicine prescription for the treatment of night blindness, poor vision, and headaches. However, the chemical components of the Shabyar tablet have not been holistically explored, which seriously hinders the discovery of the activity. This study qualitatively and quantitatively investigated the overall chemical profile of the Shabyar tablet using ultra-high-performance liquid chromatography hyphenated with quadrupole-orbitrap high-resolution mass spectrometry. Altogether, 170 chemical components, including 59 flavonoids, 78 organic acids, 12 anthranones, three anthraquinones, one naphthalene, and 17 other compounds were tentatively identified and attributed, with 40 among these being unambiguously characterized in comparison with their corresponding authentic standards. To further determine the major representative constituents of the Shabyar tablet, a quantitative method was used for the simultaneous analysis of 33 characteristic components in Shabyar samples. The results were validated in terms of linearity, precision, repeatability, stability, and recovery. This newly developed approach could be successfully employed for evaluating the holistic quality of crude extracts and Chinese medicines in the Shabyar compound tablet and provide a solid chemical foundation for additional investigations on in vivo pharmacodynamics and therapeutic mechanisms to identify the potential effective components of traditional medicines.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicina Tradicional Chinesa , Prescrições , Comprimidos/química , Espectrometria de Massas em Tandem/métodos
19.
J Math Biol ; 85(5): 49, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36222889

RESUMO

To study disease transmission with vaccination based on the network, we map an SIR model to a site-bond percolation model. In the case where the vaccination probability is zero, this model degenerates into a bond percolation model without the immunization. Using the method of generation functions, we obtain exact theoretical results for the epidemic threshold and the average outbreak size. From these exact solutions, we find that the epidemic threshold increases while the average outbreak size decreases with vaccination probability. Numerical simulations show that the size of giant component S increases with transmissibility T but decreases with the probability of vaccination. In addition, we compare the epidemic threshold and the size of the giant component for a Poisson network, an exponential network and a power-law network using numerical simulations. When the probability of vaccination is fixed, the epidemic threshold is the smallest for heterogeneous networks and the size of giant component S in homogeneous networks becomes largest for large transmissibility T(T close to 1).


Assuntos
Epidemias , Surtos de Doenças/prevenção & controle , Epidemias/prevenção & controle , Probabilidade , Vacinação
20.
Nanomedicine ; : 102610, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36257504

RESUMO

Cancer therapies are limited by poor drug penetration that impedes effective tumor treatment. This was overcome in the present study by loading the immune reaction inducing nanocarriers of the bacterial outer membrane vesicles (OMVs) and doxorubicin (DOX) into the natural immunity platform OMV via incubation. Drug accumulation at the tumor site was improved by using the targeting peptide 6-Mal- Arg-Gly-Asp (RGD) on the surface of OMVs to increase internalization via binding to cell surface integrin αvß3. OMVs stimulate immune responses by reversing the immune-suppressive tumor microenvironment (TME) via decreasing TAM and Treg, increasing CD8+ T and M1, and promoting DC maturation. The combination of DOX and OMVs compensates for the shortcomings of monotherapy (e.g., chemotherapy and immunotherapy) and amplifies the therapeutic efficacy of cancer treatment, while aiding selection of novel nanocarriers and development of effective therapeutic regimens.

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