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1.
Nature ; 623(7986): 334-339, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37758955

RESUMO

Formation of continental crust has shaped the surface and interior of our planet and generated the land and mineral resources on which we rely. However, how the early continental crust of Earth formed is still debated1-7. Modern continental crust is largely formed from wet and oxidizing arc magmas at subduction zones, in which oceanic lithosphere and water recycle into the mantle8-10. The magmatic H2O content and redox state of ancient rocks that constitute the early continental crust, however, are difficult to quantify owing to ubiquitous metamorphism. Here we combine two zircon oxybarometers11,12 to simultaneously determine magmatic oxygen fugacity (fO2) and H2O content of Archaean (4.0-2.5 billion years ago) granitoids that dominate the early continental crust. We show that most Archaean granitoid magmas were ≥1 log unit more oxidizing than Archaean ambient mantle-derived magmas13,14 and had high magmatic H2O contents (6-10 wt%) and high H2O/Ce ratios (>1,000), similar to modern arc magmas. We find that magmatic fO2, H2O contents and H2O/Ce ratios of Archaean granitoids positively correlate with depth of magma formation, requiring transport of large amounts of H2O to the lower crust and mantle. These observations can be readily explained by subduction but are difficult to reconcile with non-subduction models of crustal formation3-7. We note an increase in magmatic fO2 and H2O content between 4.0 and 3.6 billion years ago, probably indicating the onset of subduction during this period.

2.
Proc Natl Acad Sci U S A ; 121(36): e2321939121, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39186649

RESUMO

Developing an effective Staphylococcus aureus (S. aureus) vaccine has been a challenging endeavor, as demonstrated by numerous failed clinical trials over the years. In this study, we formulated a vaccine containing a highly conserved moonlighting protein, the pyruvate dehydrogenase complex E2 subunit (PDHC), and showed that it induced strong protective immunity against epidemiologically relevant staphylococcal strains in various murine disease models. While antibody responses contributed to bacterial control, they were not essential for protective immunity in the bloodstream infection model. Conversely, vaccine-induced systemic immunity relied on γδ T cells. It has been suggested that prior S. aureus exposure may contribute to the reduction of vaccine efficacy. However, PDHC-induced protective immunity still facilitated bacterial clearance in mice previously exposed to S. aureus. Collectively, our findings indicate that PDHC is a promising serotype-independent vaccine candidate effective against both methicillin-sensitive and methicillin-resistant S. aureus isolates.


Assuntos
Infecções Estafilocócicas , Vacinas Antiestafilocócicas , Staphylococcus aureus , Animais , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Camundongos , Staphylococcus aureus/imunologia , Staphylococcus aureus/enzimologia , Vacinas Antiestafilocócicas/imunologia , Complexo Piruvato Desidrogenase/metabolismo , Complexo Piruvato Desidrogenase/imunologia , Feminino , Anticorpos Antibacterianos/imunologia , Modelos Animais de Doenças , Humanos , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Camundongos Endogâmicos C57BL , Staphylococcus aureus Resistente à Meticilina/imunologia , Piruvato Desidrogenase (Lipoamida)/imunologia , Piruvato Desidrogenase (Lipoamida)/metabolismo , Piruvato Desidrogenase (Lipoamida)/genética
3.
Development ; 149(21)2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36178108

RESUMO

The efficient extraction of image data from curved tissue sheets embedded in volumetric imaging data remains a serious and unsolved problem in quantitative studies of embryogenesis. Here, we present DeepProjection (DP), a trainable projection algorithm based on deep learning. This algorithm is trained on user-generated training data to locally classify 3D stack content, and to rapidly and robustly predict binary masks containing the target content, e.g. tissue boundaries, while masking highly fluorescent out-of-plane artifacts. A projection of the masked 3D stack then yields background-free 2D images with undistorted fluorescence intensity values. The binary masks can further be applied to other fluorescent channels or to extract local tissue curvature. DP is designed as a first processing step than can be followed, for example, by segmentation to track cell fate. We apply DP to follow the dynamic movements of 2D-tissue sheets during dorsal closure in Drosophila embryos and of the periderm layer in the elongating Danio embryo. DeepProjection is available as a fully documented Python package.


Assuntos
Aprendizado Profundo , Microscopia , Microscopia/métodos , Algoritmos , Artefatos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
4.
J Virol ; 98(7): e0078624, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38916398

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) virus and hantavirus are categorized under the Bunyavirales order. The severe disease progression in both SFTS and hemorrhagic fever with renal syndrome (HFRS) is associated with cytokine storms. This study aimed to explore the differences in cytokine profiles and immune responses between the two diseases. A cross-sectional, single-center study involved 100 participants, comprising 46 SFTS patients, 48 HFRS patients, and 6 healthy controls. The study employed the Luminex cytokine detection platform to measure 48 cytokines. The differences in cytokine profiles and immune characteristics between the two diseases were further analyzed using multiple linear regression, principal component analysis, and random forest method. Among the 48 cytokines tested, 30 showed elevated levels in SFTS and/or HFRS compared to the healthy control group. Furthermore, there were 19 cytokines that exhibited significant differences between SFTS and HFRS. Random forest analysis suggested that TRAIL and CTACK were predictive of SFTS, while IL2Ralpha, MIG, IL-8, IFNalpha2, HGF, SCF, MCP-3, and PDGFBB were more common with HFRS. It was further verified by the receiver operating characteristic with area under the curve >0.8 and P-values <0.05, except for TRAIL. Significant differences were observed in the cytokine profiles of SFTS and HFRS, with TRAIL, IL2Ralpha, MIG, and IL-8 being the top 4 cytokines that most clearly distinguished the two diseases. IMPORTANCE: SFTS and HFRS differ in terms of cytokine immune characteristics. TRAIL, IL-2Ralpha, MIG, and IL-8 were the top 4 that differed markedly between SFTS and HFRS.


Assuntos
Citocinas , Febre Hemorrágica com Síndrome Renal , Febre Grave com Síndrome de Trombocitopenia , Humanos , Febre Hemorrágica com Síndrome Renal/imunologia , Febre Hemorrágica com Síndrome Renal/virologia , Febre Hemorrágica com Síndrome Renal/sangue , Citocinas/sangue , Masculino , Febre Grave com Síndrome de Trombocitopenia/imunologia , Febre Grave com Síndrome de Trombocitopenia/virologia , Pessoa de Meia-Idade , Feminino , Estudos Transversais , Adulto , Idoso , Phlebovirus/imunologia
5.
Circ Res ; 133(1): e1-e16, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37154033

RESUMO

BACKGROUND: Atrial fibrillation (AF), the most common arrhythmia, is associated with the downregulation of FKBP5 (encoding FKBP5 [FK506 binding protein 5]). However, the function of FKBP5 in the heart remains unknown. Here, we elucidate the consequences of cardiomyocyte-restricted loss of FKBP5 on cardiac function and AF development and study the underlying mechanisms. METHODS: Right atrial samples from patients with AF were used to assess the protein levels of FKBP5. A cardiomyocyte-specific FKBP5 knockdown mouse model was established by crossbreeding Fkbp5flox/flox mice with Myh6MerCreMer/+ mice. Cardiac function and AF inducibility were assessed by echocardiography and programmed intracardiac stimulation. Histology, optical mapping, cellular electrophysiology, and biochemistry were employed to elucidate the proarrhythmic mechanisms due to loss of cardiomyocyte FKBP5. RESULTS: FKBP5 protein levels were lower in the atrial lysates of patients with paroxysmal AF or long-lasting persistent (chronic) AF. Cardiomyocyte-specific knockdown mice exhibited increased AF inducibility and duration compared with control mice. Enhanced AF susceptibility in cardiomyocyte-specific knockdown mice was associated with the development of action potential alternans and spontaneous Ca2+ waves, and increased protein levels and activity of the NCX1 (Na+/Ca2+-exchanger 1), mimicking the cellular phenotype of chronic AF patients. FKBP5-deficiency enhanced transcription of Slc8a1 (encoding NCX1) via transcription factor hypoxia-inducible factor 1α. In vitro studies revealed that FKBP5 negatively modulated the protein levels of hypoxia-inducible factor 1α by competitively interacting with heat-shock protein 90. Injections of the heat-shock protein 90 inhibitor 17-AAG normalized protein levels of hypoxia-inducible factor 1α and NCX1 and reduced AF susceptibility in cardiomyocyte-specific knockdown mice. Furthermore, the atrial cardiomyocyte-selective knockdown of FKBP5 was sufficient to enhance AF arrhythmogenesis. CONCLUSIONS: This is the first study to demonstrate a role for the FKBP5-deficiency in atrial arrhythmogenesis and to establish FKBP5 as a negative regulator of hypoxia-inducible factor 1α in cardiomyocytes. Our results identify a potential molecular mechanism for the proarrhythmic NCX1 upregulation in chronic AF patients.


Assuntos
Fibrilação Atrial , Camundongos , Animais , Fibrilação Atrial/metabolismo , Regulação para Baixo , Miócitos Cardíacos/metabolismo , Hipóxia/metabolismo , Proteínas de Choque Térmico/metabolismo
6.
Nucleic Acids Res ; 51(16): 8711-8729, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37427786

RESUMO

N 6-threonylcarbamoyladenosine (t6A) is a post-transcriptional modification found uniquely at position 37 of tRNAs that decipher ANN-codons in the three domains of life. tRNA t6A plays a pivotal role in promoting translational fidelity and maintaining protein homeostasis. The biosynthesis of tRNA t6A requires members from two evolutionarily conserved protein families TsaC/Sua5 and TsaD/Kae1/Qri7, and a varying number of auxiliary proteins. Furthermore, tRNA t6A is modified into a cyclic hydantoin form of t6A (ct6A) by TcdA in bacteria. In this work, we have identified a TsaD-TsaC-SUA5-TcdA modular protein (TsaN) from Pandoraviruses and determined a 3.2 Å resolution cryo-EM structure of P. salinus TsaN. The four domains of TsaN share strong structural similarities with TsaD/Kae1/Qri7 proteins, TsaC/Sua5 proteins, and Escherichia coli TcdA. TsaN catalyzes the formation of threonylcarbamoyladenylate (TC-AMP) using L-threonine, HCO3- and ATP, but does not participate further in tRNA t6A biosynthesis. We report for the first time that TsaN catalyzes a tRNA-independent threonylcarbamoyl modification of adenosine phosphates, leading to t6ADP and t6ATP. Moreover, TsaN is also active in catalyzing tRNA-independent conversion of t6A nucleoside to ct6A. Our results imply that TsaN from Pandoraviruses might be a prototype of the tRNA t6A- and ct6A-modifying enzymes in some cellular organisms.


Assuntos
Adenosina , Ligases , RNA de Transferência , Adenosina/análogos & derivados , Adenosina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ligases/metabolismo , Modelos Moleculares , Nucleosídeos , RNA de Transferência/metabolismo
7.
Chem Soc Rev ; 53(16): 8137-8181, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39021095

RESUMO

Hydrogen peroxide (H2O2) is a highly desired chemical with a wide range of applications. Recent advancements in H2O2 synthesis center on the electrochemical reduction of oxygen, an environmentally friendly approach that facilitates on-site production. To successfully implement practical-scale, highly efficient electrosynthesis of H2O2, it is critical to meticulously explore both the design of catalytic materials and the engineering of other components of the electrochemical system, as they hold equal importance in this process. Development of promising electrocatalysts with outstanding selectivity and activity is a prerequisite for efficient H2O2 electrosynthesis, while well-configured electrolyzers determine the practical implementation of large-scale H2O2 production. In this review, we systematically summarize fundamental mechanisms and recent achievements in H2O2 electrosynthesis, including electrocatalyst design, electrode optimization, electrolyte engineering, reactor exploration, potential applications, and integrated systems, with an emphasis on active site identification and microenvironment regulation. This review also proposes new insights into the existing challenges and opportunities within this rapidly evolving field, together with perspectives on future development of H2O2 electrosynthesis and its industrial-scale applications.

8.
Nano Lett ; 24(13): 3994-4001, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38518181

RESUMO

Transforming the Pt-M alloy into an ordered intermetallic is an effective strategy to improve the electrocatalytic activity and stability toward the oxygen reduction reaction (ORR). However, the synthesis of nanosized intermetallics remains challenging. Herein, we report an efficient ORR electrocatalyst, consisting of a monodisperse nanosized PtCu intermetallic on hollow mesoporous carbon spheres (HMCS). As predicted by theoretical calculations, PtCu intermetallics exhibit beneficial electronic structure, with a low theoretical overpotential of 0.33 V and enhanced Cu stability. Resulting from the multiscale modulation of catalyst structure, the O-PtCu/HMCS catalyst delivers a high mass activity of 2.73 A cm-2Pt at 0.9 V and remarkable stability. Identical location transmission electron microscopy (IL-TEM) investigations demonstrate that the rate of carbon corrosion is alleviated on HMCS, which contributes to the long-term durability. This work provides a promising design strategy for an ORR electrocatalyst, and the IL-TEM investigations offer new perspectives for the performance enhancement mechanism.

9.
Nano Lett ; 24(18): 5467-5473, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38647318

RESUMO

The discovery of room-temperature ferromagnetism in van der Waals (vdW) materials opens new avenues for exploring low-dimensional magnetism and its applications in spintronics. Recently, the observation of the room-temperature topological Hall effect in the vdW ferromagnet Fe3GaTe2 suggests the possible existence of room-temperature skyrmions, yet skyrmions have not been directly observed. In this study, real-space imaging was employed to investigate the domain evolution of the labyrinth and skyrmion structure. First, Néel-type skyrmions can be created at room temperature. In addition, the influence of flake thickness and external magnetic field (during field cooling) on both labyrinth domains and the skyrmion lattice is unveiled. Due to the competition between magnetic anisotropy and dipole interactions, the specimen thickness significantly influences the density of skyrmions. These findings demonstrate that Fe3GaTe2 can host room-temperature skyrmions of various sizes, opening up avenues for further study of magnetic topological textures at room temperature.

10.
J Infect Dis ; 230(1): 61-66, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052731

RESUMO

BACKGROUND: Abnormal cervical cytology is commonly observed in women with human immunodeficiency virus (WWH). METHODS: A cross-sectional study was conducted with 130 WWH and 147 age-matched healthy controls, who underwent gynecological examinations at Beijing Ditan Hospital. The presence of abnormal cervical cytology in WWH was predicted after performing a logistic regression analysis. RESULTS: Multivariate logistic regression revealed 3 independent factors, among which CD4 cell count ≥350 cells/µL was the protective factor, while human papillomavirus infection and abnormal vaginal pH were the risk factors. CONCLUSIONS: Vaginal microecological disorders can increase the risk of abnormal cervical cytology in WWH.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Doenças Vaginais , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Estudos de Casos e Controles , Contagem de Linfócito CD4 , Colo do Útero/patologia , Colo do Útero/virologia , China/epidemiologia , Estudos Transversais , Infecções por HIV/complicações , Modelos Logísticos , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/complicações , Fatores de Risco , Vagina/virologia , Vagina/patologia , Doenças Vaginais/virologia , Doenças Vaginais/epidemiologia
11.
Gut ; 73(9): 1414-1420, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38906695

RESUMO

BACKGROUND AND AIMS: This study aimed to evaluate the efficacy and safety of vonoprazan and tetracycline (VT) dual therapy as first-line treatment for Helicobacter pylori infection in patients with penicillin allergy. METHODS: In this randomised controlled trial, treatment-naïve adults with H. pylori infection and penicillin allergy were randomised 1:1 to receive either open-label VT dual therapy (vonoprazan 20 mg two times per day+tetracycline 500 mg three times a day) or bismuth quadruple therapy (BQT; lansoprazole 30 mg two times per day+colloidal bismuth 150 mg three times a day+tetracycline 500 mg three times a day+metronidazole 400 mg three times a day) for 14 days. The primary outcome was non-inferiority in eradication rates in the VT dual group compared with the BQT group. Secondary outcomes included assessing adverse effects. RESULTS: 300 patients were randomised. The eradication rates in the VT group and the BQT group were: 92.0% (138/150, 95% CI 86.1% to 95.6%) and 89.3% (134/150, 95% CI 83.0% to 93.6%) in intention-to-treat analysis (difference 2.7%; 95% CI -4.6% to 10.0%; non-inferiority p=0.000); 94.5% (138/146, 95% CI 89.1% to 97.4%) and 93.1% (134/144, 95% CI 87.3% to 96.4%) in modified intention-to-treat analysis (difference 1.5%; 95% CI -4.9% to 8.0%; non-inferiority p=0.001); 95.1% (135/142, 95% CI 89.7% to 97.8%) and 97.7% (128/131, 95% CI 92.9% to 99.4%) in per-protocol analysis (difference 2.6%; 95% CI -2.9% to 8.3%; non-inferiority p=0.000). The treatment-emergent adverse events (TEAEs) were significantly lower in the VT group (14.0% vs 48.0%, p=0.000), with fewer treatment discontinuations due to TEAEs (2.0% vs 8.7%, p=0.010). CONCLUSIONS: VT dual therapy demonstrated efficacy and safety as a first-line treatment for H. pylori infection in the penicillin-allergic population, with comparable efficacy and a lower incidence of TEAEs compared with traditional BQT. TRIAL REGISTRATION NUMBER: ChiCTR2300074693.


Assuntos
Antibacterianos , Hipersensibilidade a Drogas , Quimioterapia Combinada , Infecções por Helicobacter , Helicobacter pylori , Penicilinas , Pirróis , Sulfonamidas , Tetraciclina , Humanos , Sulfonamidas/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Hipersensibilidade a Drogas/etiologia , Tetraciclina/uso terapêutico , Tetraciclina/efeitos adversos , Tetraciclina/administração & dosagem , Penicilinas/efeitos adversos , Penicilinas/uso terapêutico , Pirróis/efeitos adversos , Pirróis/uso terapêutico , Pirróis/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Adulto , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Bismuto/administração & dosagem , Inibidores da Bomba de Prótons/efeitos adversos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/uso terapêutico , Resultado do Tratamento , Idoso , Metronidazol/efeitos adversos , Metronidazol/uso terapêutico , Metronidazol/administração & dosagem , Lansoprazol/uso terapêutico , Lansoprazol/administração & dosagem , Lansoprazol/efeitos adversos
12.
J Am Chem Soc ; 146(4): 2816-2823, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38230974

RESUMO

Isolating Pd atoms has been shown to be crucial for the design of a Pd-based electrocatalyst toward 2e- oxygen reduction reaction (ORR). However, there are limited studies focusing on the systematic compositional design that leads to an optimal balance between activity and selectivity. Herein, we design a series of Au@Pd core@shell structures to investigate the influence of the Pd 4d orbital overlapping degree on 2e- ORR performance. Density functional theory (DFT) calculations indicate that enhanced H2O2 selectivity and activity are achieved at Pdn clusters with n ≤ 3, and Pd clusters larger than Pd3 should be active for 4e- ORR. However, experimental results show that Au@Pd nanowires (NWs) with Pd4 as the primary structure exhibit the optimal H2O2 performance in an acidic electrolyte with a high mass activity (7.05 A mg-1 at 0.4 V) and H2O2 selectivity (nearly 95%). Thus, we report that Pd4, instead of Pd3, is the upper threshold of Pd cluster size for an ideal 2e- ORR. It results from the oxygen coverage on the catalyst surface during the ORR process, and such an oxygen coverage phenomenon causes electron redistribution and weakened *OOH binding strength on active sites, leading to enhanced activity of Pd4 with only 0.06 V overpotential in acidic media.

13.
J Gene Med ; 26(2): e3671, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38384136

RESUMO

BACKGROUND: Head and neck squamous cell carcinoma (HNSC) is a challenging cancer with significant clinical implications. Natural killer (NK) cells have emerged as important players in tumor immunosurveillance, yet their role and potential as prognostic biomarkers in HNSC remain unclear. METHODS: Quantitative analysis using multiple algorithms identified FCRL1, KIR3DL2 and ZNF541 as molecules significantly associated with local NK cell infiltration and patient survival. A prognostic model based on these molecules demonstrated robust predictive performance. RESULTS: Analysis of high- and low-risk patient groups revealed distinct differences in the tumor microenvironment, indicating an inhibitory immune microenvironment in high-risk patients. Notably, low-risk patients exhibited potential sensitivity to immunotherapy and showed favorable responses to specific drugs such as axitinib, methotrexate, rapamycin and vorinostat. NK cells, important effectors of the innate immune response, were found to play a crucial role in HNSC immunity. The present study provides valuable insights into the correlation between FCRL1, KIR3DL2, ZNF541 and NK cell infiltration, paving the way for future investigations into their roles in HNSC. Activation of NOTCH signaling, MYC targets, DNA repair, E2F targets, epithelial-mesenchymal transition, G2M checkpoint and mitotic spindle pathways in high-risk patients suggests their involvement in disease progression and poor prognosis. CONCLUSIONS: The present study reveals the significance of NK cells in HNSC and their potential as prognostic biomarkers. The CFKZ score offers a promising approach for predicting patient outcomes and guiding personalized treatment decisions in HNSC. These findings contribute to our understanding of HNSC immunobiology and hold implications for precision medicine in HNSC management.


Assuntos
Neoplasias de Cabeça e Pescoço , Células Matadoras Naturais , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias de Cabeça e Pescoço/genética , Biomarcadores , Microambiente Tumoral
14.
Small ; : e2403490, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031997

RESUMO

The miniaturization, integration, and increased power of electronic devices have exacerbated serious heat dissipation issues. Thermally conductive adhesives, which effectively transfer heat and firmly bond components, are critical for addressing these challenges. This paper innovatively proposed a composite comprising inorganic phosphate/alumina as a matrix and diamond as filler. The composite achieved an isotropic thermal conductivity (TC) of up to 18.96 W m-1 K-1, significantly surpassing existing reports while maintaining electrical insulation. First-principles calculations and experimental tests confirmed that the high TC of phosphate and excellent interface contact ensured efficient heat transfer. To optimize bonding performance, a modified-diamond/Al(H2PO4)3@epoxy hybrid composite is subsequently developed using an organic modification method. The unique hybrid structure, combining inorganic thermal pathways and an organic adhesive network, enabled the hybrid composite to simultaneously possess a high TC (3.23 W m-1 K-1) and strong adhesion (14.35 MPa). Compared to previous reports, the comprehensive performance of this hybrid thermally conductive adhesive is exceptionally remarkable. The superior heat dissipation capability of the hybrid thermal adhesive is demonstrated in chip cooling scenarios. This organic/inorganic hybrid approach offered a new direction for obtaining advanced thermal interface materials, demonstrating significant application potential in chip soldering, packaging, and heat dissipation.

15.
Small ; 20(24): e2308286, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431926

RESUMO

The prevalence of drug-resistant bacteria presents a significant challenge to the antibiotic treatment of Helicobacter pylori (H. pylori), while traditional antimicrobial agents often suffer from shortcomings such as poor gastric retention, inadequate alleviation of inflammation, and significant adverse effects on the gut microbiota. Here, a selenized chitosan (CS-Se) modified bismuth-based metal-organic framework (Bi-MOF@CS-Se) nanodrug is reported that can target mucin through the charge interaction of the outer CS-Se layer to achieve mucosal adhesion and gastric retention. Additionally, the Bi-MOF@CS-Se can respond to gastric acid and pepsin degradation, and the exposed Bi-MOF exhibits excellent antibacterial properties against standard H. pylori as well as clinical antibiotic-resistant strains. Remarkably, the Bi-MOF@CS-Se effectively alleviates inflammation and excessive oxidative stress by regulating the expression of inflammatory factors and the production of reactive oxygen species (ROS), thereby exerting therapeutic effects against H. pylori infection. Importantly, this Bi-MOF@CS-Se nanodrug does not affect the homeostasis of gut microbiota, providing a promising strategy for efficient and safe treatment of H. pylori infection.


Assuntos
Microbioma Gastrointestinal , Helicobacter pylori , Inflamação , Estruturas Metalorgânicas , Helicobacter pylori/efeitos dos fármacos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Inflamação/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos
16.
Opt Express ; 32(3): 4111-4121, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297619

RESUMO

This article presents a terahertz (THz) fast line-scanning imaging system with three-dimensional (3-D) focus-steering capability operating at 0.1 THz. The system comprises a 3-D printed rotating multi-prism plate and a dual-device structure consisting of a negative ridge pyramid and a column ridge pyramid. The simulation and experimental results demonstrate that the system generates a sheet-shaped diffraction-free beam with a projection distance of approximately 175 mm and a diffraction-free distance of approximately 200 mm. Moreover, the system maintains a resolution greater than 4 mm within the diffraction-free range. Furthermore, the proposed THz lens-less line-scanning imaging system enables 3-D scanning imaging within a set range of ±22°. The proposed approach can be extended to cover other frequencies within the THz range by appropriately adjusting the parameters. The system has the advantages of long working distance and long depth of field, making it a very attractive candidate for low-cost, easy-fabrication, and easy-adjustment solutions for the next generation of THz fast detection and imaging technology.

17.
Opt Express ; 32(11): 18594-18604, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859012

RESUMO

Non-Hermitian systems have recently attracted significant attention in photonics due to the realization that the interplay between gain and loss can lead to entirely new and unexpected features. Here, we propose and demonstrate a non-Hermitian Faraday system capable of non-reciprocal omni-polarizer action at the exceptional point. Notably, both forward and backward propagating light with arbitrary polarization converge to the same polarization state. Leveraging the robustness and non-reciprocity of the non-Hermitian Faraday system, we realize an omni-polarized Faraday isolator that can effectively isolate any polarized light without the need for a polarizer at the incident port of backward propagation. Remarkably, under the given parameter configuration, the isolator achieves a maximum isolation ratio of approximately 100 dB and a minimum isolation ratio of around 45 dB for various polarized light, accompanied by near-zero insertion loss. Furthermore, our research reveals the remarkable tolerance of the non-Hermitian Faraday isolator to nonlinear effects. This unique characteristic allows us to harness nonlinear effects to achieve various optical functions, all while maintaining excellent isolation performance. The proposed non-Hermitian Faraday system paves the way for the realization of magnetically or optically switchable non-reciprocal devices.

18.
Opt Lett ; 49(18): 5268-5271, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39270282

RESUMO

Terahertz (THz) waves show outstanding application value in the nondestructive detection of hidden targets that are impenetrable to visible light. However, the uncertain location of hidden targets puts a higher demand on the zoom function of the THz quasi-optical systems, especially when the object is immovable. This paper proposes a continuous zoom system working in the THz band consisting of a negative axicon disk, a segmented axicon, and a freeform lens. The negative axicon disk and segmented axicon shape THz waves into annular beams with adjustable diameters, which are respectively focused at different positions by the zone-designed freeform lens. Both simulation and experimental results indicate that the zoom range of the system can reach 82 mm while maintaining an imaging resolution of 6 mm. Notably, continuous zooming is achieved by merely rotating the negative axicon disk, instead of the lens moving. Moreover, all devices in the system can be fabricated by 3D printing or machining. This approach offers the advantages of simple adjustment and low cost, providing, to our knowledge, a novel perspective for the design and application of THz quasi-optical imaging systems.

19.
Oncology ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134010

RESUMO

INTRODUCTION: Laryngeal squamous cell carcinoma (LSCC) is the most common type of laryngeal cancer, with around 60% of patients being diagnosed at an advanced stage. Recently, cancer-derived sialylated immunoglobulin G (SIA-IgG) has been suggested to play a role in the progression of various epithelial tumors, but its significance in LSCC remains unknown. This study aims to investigate the clinical significance of SIA-IgG as a novel biomarker in relation to the initiation, progression, and prognostication of LSCC. METHODS: Immunohistochemistry (IHC) were utilized to assess SIA-IgG expression in tumor samples from 75 LSCC patients, aiming to investigate its correlation with clinical prognosis. Vitro functional experiments were conducted to explore the impact of SIA-IgG expression on the proliferative and migratory abilities of laryngocarcinoma cells. RESULTS: High expression of SIA-IgG was associated with pT stage, pN stage, TNM stage, and recurrence during follow-up, and was correlated with poor disease-free survival (DFS) and overall survival (OS). Multivariate Cox analysis demonstrated that SIA-IgG served as an independent risk factor for OS and DFS. Knocking down SIA-IgG significantly weakened laryngocarcinoma cells' proliferation, clonogenesis, and migration abilities. CONCLUSIONS: The frequent expression of SIA-IgG in LSCC is significantly associated with poor prognosis. High levels of SIA-IgG can enhance proliferation and migration in laryngocarcinoma cells. These findings suggest that SIA-IgG has potential as a novel biomarker for LSCC.

20.
Exp Eye Res ; 240: 109814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307190

RESUMO

Neurotrophic keratopathy (NK) is a challenging disease with the reduced innervation to the cornea. To establish a genetic and stable mouse model of NK, we utilized the TRPV1-DTR mice with intraperitoneal injection of diphtheria toxin (DT) to selectively eliminate TRPV1 neurons. After DT administration, the mice exhibited robust ablation of TRPV1 neurons in the trigeminal ganglion, accompanied with reduced corneal sensation and nerve density, as well as the decreased calcitonin-gene-related peptide (CGRP) and substance P levels. According to disease progression of TRPV1 neuronal ablation, tear secretion was reduced from day 3, which followed by corneal epithelial punctate lesions from day 7. From day 11 to day 16, the mice exhibited persistent corneal epithelial defects and stromal edema. By day 21, corneal ulceration and stromal melting were observed with the abundant inflammatory cell infiltration, corneal neovascularization, and enhanced cell apoptosis. Moreover, subconjunctival injection of CGRP delayed the NK progression with the characteristics of reduced severe corneal epithelial lesions and corneal inflammation. In addition, the impairments of conjunctival goblet cells, lacrimal gland, and meibomian gland were identified by the diminished expression of MUC5AC, AQP5, and PPARγ, respectively. Therefore, these results suggest that the TRPV1-DTR mice may serve as a reliable animal model for the research of NK pathogenesis.


Assuntos
Distrofias Hereditárias da Córnea , Ceratite , Doenças do Nervo Trigêmeo , Camundongos , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Córnea/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
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