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1.
Neural Regen Res ; 20(2): 557-573, 2025 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38819067

RESUMO

JOURNAL/nrgr/04.03/01300535-202502000-00032/figure1/v/2024-05-28T214302Z/r/image-tiff Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury. Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction. However, the mechanisms involved remain unclear. In this study, we found that after spinal cord injury, resting microglia (M0) were polarized into pro-inflammatory phenotypes (MG1 and MG3), while resting astrocytes were polarized into reactive and scar-forming phenotypes. The expression of growth arrest-specific 6 (Gas6) and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury. In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia, and even inhibited the cross-regulation between them. We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway. This, in turn, inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways. In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord, thereby promoting tissue repair and motor function recovery. Overall, Gas6 may play a role in the treatment of spinal cord injury. It can inhibit the inflammatory pathway of microglia and polarization of astrocytes, attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment, and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

2.
ACS Appl Mater Interfaces ; 16(37): 49973-49984, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39230980

RESUMO

Creating diverse microparticle patterns on a large scale enhances the performance and efficiency of biochemical analytics. Current techniques exhibit limitations in achieving diverse microparticle patterns on a large scale, primarily focusing on patterning particles of the same type with limited flexibility and accessibility. Moreover, accessibility to patterned particles without a fixed formation poses additional challenges. Herein, in this work, we introduce a novel robotic micropatterning system designed to address these challenges. The system facilitates the selection, batch transferring, patterning, and encapsulation of microparticles using negative dielectrophoresis (nDEP)-tweezers, enabling large-scale microparticle patterning on a hydrogel. A multielectrode chip was mounted on a micromanipulator to serve as the nDEP tweezers, and the microparticles scattering on the substrate could be trapped and displaced to different positions on a substrate with an array of holes for large-scale pattern generation. Photosensitive hydrogel was employed for microparticle pattern encapsulation. The effects of configuring different experimental parameters on the patterning efficiency were evaluated and analyzed. Experiments were conducted to explore the stability and performance of the micropatterns. Various patterns with hydrogel encapsulation were created using different color polystyrene microbeads (orange, blue, and green) with varying sizes (50, 100, and 125 µm) under the adjusted environment. Results demonstrate the successful creation of large-scale microbead patterns in a specified form and their encapsulation into an extractable hydrogel using the proposed nDEP tweezer system. The proposed system can be potentially applied to diverse bioparticles for analysis.

3.
J Thorac Dis ; 16(8): 5073-5085, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39268112

RESUMO

Background: Acute myocardial infarction (AMI) is the most severe manifestation of coronary heart disease (CHD), and timely and effective opening of the culprit vessels has been effective in reducing its mortality, but long-term death still threatens the life of patients. Therefore, finding biomarkers to predict death post-myocardial infarction (MI) is crucial. The aim of our study is to find biomarkers that predicted long-term death in Chinese AMI patients. Methods: This retrospective analysis included patients with AMI from 1 January 2017 to 30 September 2019. All patients were followed up at least 4 years. Propensity score matching was used to mitigate the influence of nonrandom selection in MI-survival and MI-death groups. Cox analysis was applied for analyzing the risk factors of death post-MI. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of biomarkers. Results: Of the 1,059 AMI patients analyzed, 130 died during follow-up. After propensity matching, there were 116 patients in each of the two groups. In addition to the traditional risk factors for long-term death post-MI, two important risk factors platelet distribution width (PDW) [hazard ratio (HR) =1.210, 95% confidence interval (CI): 1.080-1.356, P=0.001] and fibrinogen (HR =1.218, 95% CI: 1.027-1.444, P=0.02) were found. The area under the curve (AUC) of PDW and fibrinogen was 0.604 (P=0.007) and 0.684 (P<0.001) respectively. The optimal thresholds were 13.05% and 3.562 g/L respectively. Conclusions: PDW and fibrinogen seem to be useful as biomarkers for long-term death prediction post-MI. The current research provides new insight into the prevention and treatment of death in Chinese patients post-MI.

4.
Nanotechnology ; 35(49)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39137800

RESUMO

Line edge roughness (LER) has been an important issue in the nanofabrication research, especially in integrated circuits. Despite numerous research studies has made efforts on achieving smaller LER value, a strategy to achieve sub-nanometer level LER still remains challenging due to inability to deposit energy with a profile of sub-nanometer LER. In this work, we introduce a strategy to fabricate structures with sub-nanometer LER, specifically, we use scanning helium ion beam to expose hydrogen silsesquioxane (HSQ) resist on thin SiNx membrane (∼20 nm) and present the 0.16 nm spatial imaging resolution based on this suspended membrane geometric construction, which is characterized by scanning transmission electron microscope (STEM). The suspended membrane serves as an energy filter of helium ion beam and due to the elimination of backscattering induced secondary electrons, we can systematically study the factors that influences the LER of the fabricated nanostructures. Furthermore, we explore the parameters including step size, designed exposure linewidth (DEL), delivered dosage and resist thickness and choosing the high contrast developer, the process window allows to fabricate lines with 0.2 nm LER is determined. AFM measurement and simulation work further reveal that at specific beam step size and DEL, the nanostructures with minimum LER can only be fabricated at specific resist thickness and dosage.

5.
Chemistry ; : e202402572, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167364

RESUMO

Encapsulation of transition metals represents a crucial method for modifying the electronic structure and regulating the reactivity of fullerene, thereby expanding its applications. Herein, we present calculations with density functional theory methods to investigate the mechanisms of the Diels-Alder (DA) reactions of cyclopentadiene and La@C60 or Gd@C60 as well as their tricationic derivatives. Our findings indicate that the encapsulation of La and Gd into the C60 cage is thermodynamically favorable. The DA reactions are favored by the presence of La and Gd, with lower barriers, though the regioselectivity, favoring 6-6 bonds in the fullerene, is not affected. The effect of external electric fields has been also considered.

6.
ACS Sens ; 9(8): 3979-3985, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39093667

RESUMO

Metal oxide gas sensors (MOGS), crucial components in monitoring air quality and detecting hazardous gases, are well known for their poisoning effects when exposed to certain gas molecules, such as hydrogen sulfide. Surprisingly, our research reveals that high-temperature H2S treatment leads to an enhancement effect rather than response decay. This study investigates the time-decaying response enhancement, being attributed to the formation of metal sulfide and metal sulfate on the metal oxide's surface, enhancing the electronic sensitization. Such an enhancement effect is demonstrated for various gases, including CO, CH3CH2OH, CH4, HCHO, and NH3. Additionally, the impacts of H2S treatment on the response and recovery time are also observed. Surface compositional analysis are conducted with X-ray photoelectron spectroscopy. A proposed mechanism for the enhancement effect is elaborated, highlighting the role of electronic sensitization and the sulfide-sulfate component. This research offers valuable insights into the potential applications of metal oxide sensors in sulfide-presented harsh environments in gas sensing, encouraging future exploration of optimized sensor materials, operation temperature, and the development of hydrogen sulfide poisoning-resistant and higher sensitivity MOGS.


Assuntos
Gases , Sulfeto de Hidrogênio , Óxidos , Sulfeto de Hidrogênio/análise , Óxidos/química , Gases/química , Gases/análise , Temperatura Alta , Metais/química
8.
Natl Sci Rev ; 11(8): nwae219, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39131924

RESUMO

The coupling of high-capacity cathodes and lithium metal anodes promises to be the next generation of high-energy-density batteries. However, the fast-structural degradations of the cathode and anode challenge their practical application. Herein, we synthesize an electrolyte additive, tris(2,2,3,3,3-pentafluoropropyl) borane (TPFPB), for ultra-stable lithium (Li) metal||Ni-rich layered oxide batteries. It can be preferentially adsorbed on the cathode surface to form a stable (B and F)-rich cathode electrolyte interface film, which greatly suppresses the electrolyte-cathode side reactions and improves the stability of the cathode. In addition, the electrophilicity of B atoms in TPFPB enhances the solubility of LiNO3 by 30 times in ester electrolyte to significantly improve the stability of the Li metal anode. Thus, the Li||Ni-rich layered oxide full batteries using TPFPB show high stability and an ultralong cycle life (up to 1500 cycles), which also present excellent performance even under high voltage (4.8 V), high areal mass loading (30 mg cm-2) and wide temperature range (-30∼60°C). The Li||LiNi0.9Co0.05Mn0.05O2 (NCM90) pouch cell using TPFPB with a capacity of 3.1 Ah reaches a high energy density of 420 Wh kg-1 at 0.1 C and presents outstanding cycling performance.

9.
Cardiovasc Diabetol ; 23(1): 303, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152461

RESUMO

BACKGROUND: Patients with diabetes have an increased risk of developing heart failure with preserved ejection fraction (HFpEF). This study aimed to compare indices of myocardial deformation and perfusion between patients with type 2 diabetes mellitus (T2DM) with and without HFpEF and to investigate the relationship between myocardial strain and perfusion reserve. METHODS: This study included 156 patients with T2DM without obstructive coronary artery disease (CAD) and 50 healthy volunteers who underwent cardiac magnetic resonance (CMR) examination at our center. Patients with T2DM were subdivided into the T2DM-HFpEF (n = 74) and the T2DM-non-HFpEF (n = 82) groups. The parameters of left ventricular (LV) and left atrial (LA) strain as well as stress myocardial perfusion were compared. The correlation between myocardial deformation and perfusion parameters was also assessed. Mediation analyses were used to evaluate the direct and indirect effects of T2DM on LA strain. RESULTS: Patients with T2DM and HFpEF had reduced LV radial peak systolic strain rate (PSSR), LV circumferential peak diastolic strain rate (PDSR), LA reservoir strain, global myocardial perfusion reserve index (MPRI), and increased LA booster strain compared to patients with T2DM without HFpEF (all P < 0.05). Furthermore, LV longitudinal PSSR, LA reservoir, and LA conduit strain were notably impaired in patients with T2DM without HFpEF compared to controls (all P < 0.05), but LV torsion, LV radial PSSR, and LA booster strain compensated for these alterations (all P < 0.05). Multivariate linear regression analysis demonstrated that LA reservoir and LA booster strain were independently associated with global MPRI (ß = 0.259, P < 0.001; ß = - 0.326, P < 0.001, respectively). Further, the difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI. Global stress PI, LA booster, global rest PI, and global MPRI showed high accuracy in diagnosing HFpEF among patients with T2DM (areas under the curve [AUC]: 0.803, 0.790, 0.740, 0.740, respectively). CONCLUSIONS: Patients with T2DM and HFpEF exhibited significant LV systolic and diastolic deformation, decreased LA reservoir strain, severe impairment of myocardial perfusion, and elevated LA booster strain that is a compensatory response in HFpEF. Global MPRI was identified as an independent influencing factor on LA reservoir and LA booster strain. The difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI, suggesting a possible mechanistic link between microcirculation impairment and cardiac dysfunction in diabetes. Myocardial perfusion and LA strain may prove valuable for diagnosing and managing HFpEF in the future.


Assuntos
Função do Átrio Esquerdo , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Imagem Cinética por Ressonância Magnética , Imagem de Perfusão do Miocárdio , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Imagem de Perfusão do Miocárdio/métodos , Idoso , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/diagnóstico , Circulação Coronária , Estudos de Casos e Controles , Contração Miocárdica
10.
FASEB J ; 38(15): e23852, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39101942

RESUMO

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative ailment that causes slow cartilage degeneration, aberrant bone remodeling, and persistent discomfort, leading to a considerable reduction in the patient's life quality. Current treatment options for TMJOA have limited efficacy. This investigation aimed to explore a potential strategy for halting or reversing the progression of TMJOA through the utilization of exosomes (EXOs) derived from urine-derived stem cells (USCs). The USC-EXOs were obtained through microfiltration and ultrafiltration techniques, followed by their characterization using particle size analysis, electron microscopy, and immunoblotting. Subsequently, an in vivo model of TMJOA induced by mechanical force was established. To assess the changes in the cartilage of TMJOA treated with USC-EXOs, we performed histology analysis using hematoxylin-eosin staining, immunohistochemistry, and histological scoring. Our findings indicate that the utilization of USC-EXOs yields substantial reductions in TMJOA, while concurrently enhancing the structural integrity and smoothness of the compromised condylar cartilage surface. Additionally, USC-EXOs exhibit inhibitory effects on osteoclastogenic activity within the subchondral bone layer of the condylar cartilage, as well as attenuated apoptosis in the rat TMJ in response to mechanical injury. In conclusion, USC-EXOs hold considerable promise as a potential therapeutic intervention for TMJOA.


Assuntos
Exossomos , Osteoartrite , Articulação Temporomandibular , Exossomos/metabolismo , Animais , Osteoartrite/terapia , Osteoartrite/patologia , Osteoartrite/metabolismo , Ratos , Masculino , Humanos , Articulação Temporomandibular/metabolismo , Articulação Temporomandibular/patologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Ratos Sprague-Dawley , Urina/citologia , Transtornos da Articulação Temporomandibular/terapia , Transtornos da Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/patologia , Feminino , Cartilagem Articular/patologia , Cartilagem Articular/metabolismo
11.
Front Endocrinol (Lausanne) ; 15: 1430720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39076513

RESUMO

Background: Bile acids (BAs), products of gut microbiota metabolism, have long been implicated in atherosclerotic disease pathogenesis. Characterizing the serum bile acid profile and exploring its potential role in carotid atherosclerosis (CAS) development are crucial tasks. Methods: In this study, we recruited 73 patients with CAS as the disease group and 77 healthy individuals as the control group. We systematically measured the serum concentrations of 15 bile acids using ultrahigh-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Multivariate logistic regression and least absolute shrinkage and selection operator (LASSO) regression were applied to analyze the impact of bile acids on the disease and select the key BAs. The possible molecular mechanism was elucidated by network pharmacology. Results: (1) The BA profile of patients with CAS significantly differed. (2) Multifactorial logistic regression analysis identified elevated levels of GCDCA (OR: 1.01, P < 0.001), DCA (OR: 1.01, P = 0.005), and TDCA (OR: 1.05, P = 0.002) as independent risk factors for CAS development. Conversely, GCA (OR: 0.99, P = 0.020), LCA (OR: 0.83, P = 0.002), and GUDCA (OR: 0.99, P = 0.003) were associated with protective effects against the disease. GCA, DCA, LCA, and TDCA were identified as the four key BAs. (3) TNF, FXR, GPBAR1, ESR1 and ACE were predicted to be targets of BAs against AS. These four BAs potentially impact AS progression by triggering signaling pathways, including cAMP, PPAR, and PI3K-AKT pathways, via their targets. Conclusion: This study offers valuable insights into potential therapeutic strategies for atherosclerosis that target bile acids.


Assuntos
Ácidos e Sais Biliares , Doenças das Artérias Carótidas , Metabolômica , Farmacologia em Rede , Humanos , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/sangue , Masculino , Feminino , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/tratamento farmacológico , Doenças das Artérias Carótidas/sangue , Pessoa de Meia-Idade , Metabolômica/métodos , Idoso , Estudos de Casos e Controles , Biomarcadores/sangue , Receptores Acoplados a Proteínas G/metabolismo , Espectrometria de Massas em Tandem
12.
Nat Commun ; 15(1): 6106, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030235

RESUMO

Stretchable electronics commonly assemble multiple material modules with varied bulk moduli and surface chemistry on one packaging substrate. Preventing the strain-induced delamination between the module and the substrate has been a critical challenge. Here we develop a packaging substrate that delivers mechanically stable module/substrate interfaces for a broad range of stiff and stretchable modules with varied surface chemistries. The key design of the substrate was to introduce module-specific stretchability and universal adhesiveness by regionally tuning the bulk molecular mobility and surface molecular polarity of a near-hermetic elastic polymer matrix. The packaging substrate can customize the deformation of different modules while avoiding delamination upon stretching up to 600%. Based on this substrate, we fabricated a fully stretchable bioelectronic device that can serve as a respiration sensor or an electric generator with an in vivo lifetime of 10 weeks. This substrate could be a versatile platform for device assembly.

13.
Small ; : e2403775, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949055

RESUMO

Despite the challenges associated with the synthesis of flexible metal-covalent organic frameworks (MCOFs), these offer the unique advantage of maximizing the atomic utilization efficiency. However, the construction of flexible MCOFs with flexible building units or linkages has rarely been reported. In this study, novel flexible MCOFs are constructed using flexible building blocks and copper clusters with hydrazone linkages. The heterometallic frameworks (Cu, Co) are prepared through the hydrazone linkage coordination method and evaluated as catalysts for the oxygen evolution reaction (OER). Owing to the spatial separation and functional cooperation of the heterometallic MCOF catalysts, the as-synthesized MCOFs exhibited outstanding catalytic activities with an overpotential of 268.8 mV at 10 mA cm-2 for the OER in 1 M KOH, which is superior to those of the reported covalent organic frameworks (COFs)-based OER catalysts. Theoretical calculations further elucidated the synergistic effect of heterometallic active sites within the linkages and frameworks, contributing to the enhanced OER activity. This study thus introduces a novel approach to the fundamental design of flexible MCOF catalysts for the OER, emphasizing their enhanced atomic utilization efficiency.

14.
Genes Dis ; 11(5): 101106, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39022129

RESUMO

Programmed cell death 2 (PDCD2) is related to cancer progression and chemotherapy sensitivity. The role of PDCD2 in solid cancers (excluding hematopoietic malignancies) and their diagnosis and prognosis remains unclear. The TCGA, CGGA, GEPIA, cBioPortal, and GTEx databases were analyzed for expression, prognostic value, and genetic modifications of PDCD2 in cancer patients. Functional enrichment analysis, CCK8, colony formation assay, transwell assay, and xenograft tumor model were undertaken to study the PDCD2's biological function in glioma (GBMLGG). The PDCD2 gene was associated with solid cancer progression. In the functional enrichment analysis results, PDCD2 was shown to participate in several important GBMLGG biological processes. GBMLGG cells may be inhibited in their proliferation, migration, invasion, and xenograft tumor growth by knocking down PDCD2. Our research can provide new insights into solid cancer prognostic biomarkers of PDCD2.

15.
Sci Data ; 11(1): 789, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019912

RESUMO

Brain metastases (BMs) and high-grade gliomas (HGGs) are the most common and aggressive types of malignant brain tumors in adults, with often poor prognosis and short survival. As their clinical symptoms and image appearances on conventional magnetic resonance imaging (MRI) can be astonishingly similar, their accurate differentiation based solely on clinical and radiological information can be very challenging, particularly for "cancer of unknown primary", where no systemic malignancy is known or found. Non-invasive multiparametric MRI and radiomics offer the potential to identify these distinct biological properties, aiding in the characterization and differentiation of HGGs and BMs. However, there is a scarcity of publicly available multi-origin brain tumor imaging data for tumor characterization. In this paper, we introduce a multi-center, multi-origin brain tumor MRI (MOTUM) imaging dataset obtained from 67 patients: 29 with high-grade gliomas, 20 with lung metastases, 10 with breast metastases, 2 with gastric metastasis, 4 with ovarian metastasis, and 2 with melanoma metastasis. This dataset includes anonymized DICOM files alongside processed FLAIR, T1-weighted, contrast-enhanced T1-weighted, T2-weighted sequences images, segmentation masks of two tumor regions, and clinical data. Our data-sharing initiative is to support the benchmarking of automated tumor segmentation, multi-modal machine learning, and disease differentiation of multi-origin brain tumors in a multi-center setting.


Assuntos
Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Glioma/patologia , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Melanoma/diagnóstico por imagem , Melanoma/patologia
16.
Micromachines (Basel) ; 15(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39064354

RESUMO

In microfluidic systems, it is important to maintain flow stability to execute various functions, such as chemical reactions, cell transportation, and liquid injection. However, traditional flow sources, often bulky and prone to unpredictable fluctuations, limit the portability and broader application of these systems. Existing fluidic stabilizers, typically designed for specific flow sources, lack reconfigurability and adaptability in terms of the stabilization ratios. To address these limitations, a modular and standardized stabilizer system with tunable stabilization ratios is required. In this work, we present a Lego-like modular microfluidic stabilizer system, which is fabricated using 3D printing and offers multi-level stabilization combinations and customizable stabilization ratios through the control of fluidic RC constants, making it adaptable to various microfluidic systems. A simplified three-element circuit model is used to characterize the system by straightforwardly extracting the RC constant without intricate calculations of the fluidic resistance and capacitance. By utilizing a simplified three-element model, the stabilizer yields two well-fitted operational curves, demonstrating an R-square of 0.95, and provides an optimal stabilization ratio below 1%. To evaluate the system's effectiveness, unstable input flow at different working frequencies is stabilized, and droplet generation experiments are conducted and discussed. The results show that the microfluidic stabilizer system significantly reduces flow fluctuations and enhances droplet uniformity. This system provides a new avenue for microfluidic stabilization with a tunable stabilization ratio, and its plug-and-play design can be effectively applied across diverse applications to finely tune fluid flow behaviors in microfluidic devices.

17.
Langmuir ; 40(31): 16113-16120, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39051840

RESUMO

The field of artificial photosynthesis, which focuses on harnessing solar light for the conversion of CO2 to economically valuable chemical products, remains a captivating area of research. In this study, we developed a series of photocatalysts based on Earth abundant elements (Fe, Co, Ni, Cu, and Zn) incorporated into 2D metalloporphyrin-conjugated organic polymers known as MTBPP-BEPA-COPs. These photocatalysts were utilized for the photoreduction of CO2 employing only H2O as the electron donor, without the need for any sacrificial agents or precious-metal cocatalysts. Remarkably, all of the synthesized MTBPP-BEPA-COPs exhibited an exceptional CO2 photoreduction performance only irradiated by visible light. Particularly, upon optimizing the metal ion coordinated with porphyrin units, ZnTBPP-BEPA-COP outperformed the other MTBPP-BEPA-COPs in terms of photocatalytic activity, achieving an impressive CO reduction yield of 152.18 µmol g-1 after just 4 h of irradiation. The electrostatic potential surfaces calculated by density functional theory suggest the potential involvement of metal centers as binding and catalytic sites for the binding of CO2. The calculated adsorption energy of CO2 with ZnTBPP-BEPA-COP exhibited one of the two smallest values. This may be the reason for the excellent catalytic effect of ZnTBPP-BEPA-COP. Thus, the present study not only demonstrates the potential of porphyrin-based conjugated polymers as highly efficient photocatalysts for CO2 reduction but also offers valuable insights into the rational design of such materials in the future.

18.
Small Methods ; : e2400707, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38923411

RESUMO

For N-type tunnel-oxide-passivated-contact silicon solar cells, optimal Ag/Al-Si contact interface is crucial to improve the efficiency. However, the specific roles of Ag and Al at the interface have not been clearly elucidated. Hence, this work delves into the sintering process of Ag/Al paste and examines the impact of the Ag/Al-Si interface structure on contact quality. By incorporating TeO2 into PbO-based Ag/Al paste, the Ag/Al-Si interface structure can be modulated. It can be found that TeO2 accelerates the sintering of Ag powder and increases Ag colloids within glass layer, while it simultaneously impedes the diffusion of molten Al. It leads to a reduced Al content near the Ag/Al-Si interface and a shorter diffusion distance of Al into Si. Notably, it can be demonstrated that the diffusion of Al in Si layer is more effective to reduce the contact resistance than the precipitation of Ag colloids. Therefore, the PbO-based Ag/Al paste, which favors Al diffusion, leads to solar cells with lower contact resistance and series resistance, higher fill factor, and superior photoelectric conversion efficiency. In brief, this work is significant for optimizing metallization of silicon solar cells and other semiconductor devices.

19.
Aging (Albany NY) ; 16(11): 9876-9898, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38843385

RESUMO

Estrogen is thought to have a role in slowing down aging and protecting cardiovascular and cognitive function. However, high doses of estrogen are still positively associated with autoimmune diseases and tumors with systemic inflammation. First, we administered exogenous estrogen to female mice for three consecutive months and found that the aorta of mice on estrogen develops inflammatory manifestations similar to Takayasu arteritis (TAK). Then, in vitro estrogen intervention was performed on mouse aortic vascular smooth muscle cells (MOVAS cells). Stimulated by high concentrations of estradiol, MOVAS cells showed decreased expression of contractile phenotypic markers and increased expression of macrophage-like phenotypic markers. This shift was blocked by tamoxifen and Krüppel-like factor 4 (KLF4) inhibitors and enhanced by Von Hippel-Lindau (VHL)/hypoxia-inducible factor-1α (HIF-1α) interaction inhibitors. It suggests that estrogen-targeted regulation of the VHL/HIF-1α/KLF4 axis induces phenotypic transformation of vascular smooth muscle cells (VSMC). In addition, estrogen-regulated phenotypic conversion of VSMC to macrophages is a key mechanism of estrogen-induced vascular inflammation, which justifies the risk of clinical use of estrogen replacement therapy.


Assuntos
Estrogênios , Subunidade alfa do Fator 1 Induzível por Hipóxia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Macrófagos , Músculo Liso Vascular , Proteína Supressora de Tumor Von Hippel-Lindau , Animais , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/efeitos dos fármacos , Feminino , Estrogênios/farmacologia , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Fenótipo , Aorta/patologia , Aorta/efeitos dos fármacos , Inflamação/metabolismo
20.
Opt Express ; 32(11): 20080-20091, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859125

RESUMO

Metasurfaces have demonstrated remarkable capabilities in manipulating light fields across diverse applications. However, current research tends to examine these functionalities in isolation, prompting a growing interest in integrating different functionalities within a singular metasurface device. In this paper, we propose and experimentally demonstrate a bifunctional metasurface capable of providing concealment and sensing functions simultaneously. Specifically, the proposed nanostructure effectively operates as a one-way mirror, exhibiting an average reflection rate of approximately 90% under external illumination, alongside an absorption rate of 87.9% from the opposite direction of incidence. This functionality renders it suitable for privacy-enhancing building windows. Meanwhile, this nanostructure also integrates liquid sensing capabilities boasting a sensitivity of 464 nm/RIU, which is particularly valuable for monitoring liquid-based corrosion. The experimental performance of the prepared 6-inch nanohole-patterned metasurface closely aligns with the simulations, and the utilization of flexible polyethylene terephthalate (PET) film, coupled with nanoimprint lithography technology, enables a direct and cost-effective manufacturing process that can be scaled up for widespread applications.

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