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1.
Br J Cancer ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266624

RESUMO

BACKGROUND: Temozolomide (TMZ) is the first-line chemotherapeutic drug for gliomas treatment. However, the clinical efficacy of TMZ in glioma patients was very limited. Therefore, it is urgently needed to discover a novel approach to increase the sensitivity of glioma cells to TMZ. METHODS: Western blot, immunohistochemical staining, and qRT-PCR assays were used to explore the mechanisms underlying TMZ promoting DKK1 expression and andrographolide (AND) inhibiting DKK1 expression. HPLC was used to detect the ability of andrographolide (AND) to penetrate the blood-brain barrier. MTT assay, bioluminescence images, magnetic resonance imaging (MRI) and H&E staining were employed to measure the proliferative activity of glioma cells and the growth of intracranial tumors. RESULTS: TMZ can promote DKK1 expression in glioma cells and brain tumors of an orthotopic model of glioma. DKK1 could promote glioma cell proliferation and tumor growth in an orthotopic model of glioma. Mechanistically, TMZ increased EGFR expression and subsequently induced the activation of its downstream MEK-ERK and PI3K-Akt pathways, thereby promoting DKK1 expression in glioma cells. Andrographolide inhibited TMZ-induced DKK1 expression through inactivating MEK-ERK and PI3K-Akt pathways. Andrographolide can cross the blood-brain barrier, the combination of TMZ and andrographolide not only improved the anti-tumor effects of TMZ but also showed a survival benefit in an orthotopic model of glioma. CONCLUSION: Andrographolide can enhance anti-tumor activity of TMZ against glioma by inhibiting DKK1 expression.

2.
Small ; 20(23): e2310184, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148310

RESUMO

Aqueous potassium-ion batteries (AKIBs) are considered promising electrochemical energy storage systems owing to their high safety and cost-effectiveness. However, the structural degradation resulting from the repeated accommodation of large K-ions and the dissolution of active electrode materials in highly dielectric aqueous electrolytes often lead to unsatisfactory electrochemical performance. This study introduces a high-entropy Prussian blue analog (HEPBA) cathode material for AKIBs, demonstrating significantly enhanced structural stability and reduced dissolution. The HEPBA exhibits a highly reversible specific capacity of 102.4 mAh g-1, with 84.4% capacity retention after undergoing 3448 cycles over a duration of 270 days. Mechanistic insights derived from comprehensive experimental investigations, supported by theoretical calculations, reveal that the HEPBA features a robust structure resistant to dissolution, a solid-solution reaction pathway with negligible volume variation during charge-discharge, and efficient ion transport kinetics characterized by a reduced band gap and a low energy barrier. This study represents a measurable step forward in the development of long-lasting electrode materials for aqueous AKIBs.

3.
BMC Pulm Med ; 24(1): 237, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745191

RESUMO

BACKGROUND: Diabetes mellitus (DM) can aggravate lung ischemia-reperfusion (I/R) injury and is a significant risk factor for recipient mortality after lung transplantation. Metformin protects against I/R injury in a variety of organs. However, the effect of metformin on diabetic lung I/R injury remains unclear. Therefore, this study aimed to observe the effect and mechanism of metformin on lung I/R injury following lung transplantation in type 2 diabetic rats. METHODS: Sprague-Dawley rats were randomly divided into the following six groups: the control + sham group (CS group), the control + I/R group (CIR group), the DM + sham group (DS group), the DM + I/R group (DIR group), the DM + I/R + metformin group (DIRM group) and the DM + I/R + metformin + Compound C group (DIRMC group). Control and diabetic rats underwent the sham operation or left lung transplantation operation. Lung function, alveolar capillary permeability, inflammatory response, oxidative stress, necroptosis and the p-AMPK/AMPK ratio were determined after 24 h of reperfusion. RESULTS: Compared with the CIR group, the DIR group exhibited decreased lung function, increased alveolar capillary permeability, inflammatory responses, oxidative stress and necroptosis, but decreased the p-AMPK/AMPK ratio. Metformin improved the function of lung grafts, decreased alveolar capillary permeability, inflammatory responses, oxidative stress and necroptosis, and increased the p-AMPK/AMPK ratio. In contrast, the protective effects of metformin were abrogated by Compound C. CONCLUSIONS: Metformin attenuates lung I/R injury and necroptosis through AMPK pathway in type 2 diabetic lung transplant recipient rats.


Assuntos
Proteínas Quinases Ativadas por AMP , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Transplante de Pulmão , Metformina , Necroptose , Traumatismo por Reperfusão , Animais , Ratos , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/etiologia , Lesão Pulmonar/metabolismo , Metformina/farmacologia , Necroptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
4.
Int J Mol Sci ; 25(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39201530

RESUMO

The rise of antibiotic tolerance in bacteria harboring genetic elements conferring resistance to antibiotics poses an increasing threat to public health. However, the primary factors responsible for the emergence of antibiotic tolerance and the fundamental molecular mechanisms involved remain poorly comprehended. Here, we demonstrate that the commonly utilized food additive Benzaldehyde (BZH) possesses the capacity to induce a significant level of fluoroquinolone tolerance in vitro among resistant Escherichia coli. Our findings from animal models reveal that the pre-administration of BZH results in an ineffective eradication of bacteria through ciprofloxacin treatment, leading to similar survival rates and bacterial loads as observed in the control group. These results strongly indicate that BZH elicits in vivo tolerance. Mechanistic investigations reveal several key factors: BZH inhibits the formation of bacterial flagella and releases proton motive force (PMF), which aids in expelling antibiotics from within cells to reducing their accumulation inside. In addition, BZH suppresses bacterial respiration and inhibits the production of reactive oxygen species (ROS). Moreover, exogenous pyruvate successfully reverses BZH-induced tolerance and restores the effectiveness of antibiotics, highlighting how crucial the pyruvate cycle is in combating antibiotic tolerance. The present findings elucidate the underlying mechanisms of BZH-induced tolerance and highlight potential hazards associated with the utilization of BZH.


Assuntos
Antibacterianos , Benzaldeídos , Escherichia coli , Flagelos , Benzaldeídos/farmacologia , Flagelos/efeitos dos fármacos , Flagelos/metabolismo , Antibacterianos/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Escherichia coli/genética , Aditivos Alimentares/farmacologia , Aditivos Alimentares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Camundongos , Testes de Sensibilidade Microbiana
5.
Hepatobiliary Pancreat Dis Int ; 22(4): 346-351, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37019775

RESUMO

Hepatocellular carcinoma (HCC) is a common malignant tumor. At present, early diagnosis of HCC is difficult and therapeutic methods are limited. Radiomics can achieve accurate quantitative evaluation of the lesions without invasion, and has important value in the diagnosis and treatment of HCC. Radiomics features can predict the development of cancer in patients, serve as the basis for risk stratification of HCC patients, and help clinicians distinguish similar diseases, thus improving the diagnostic accuracy. Furthermore, the prediction of the treatment outcomes helps determine the treatment plan. Radiomics is also helpful in predicting the HCC recurrence, disease-free survival and overall survival. This review summarized the role of radiomics in the diagnosis, treatment and prognosis of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Prognóstico , Humanos , Valor Preditivo dos Testes
6.
Int J Mol Sci ; 24(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36614202

RESUMO

Leaves are an essential and unique organ of plants, and many studies have proved that auxin has significant impacts on the architecture of leaves, thus the manipulation of the three-dimensional structure of a leaf could provide potential strategies for crop yields. In this study, 32 basic leucine zipper transcription factors (bZIP TFs) which responded to 50 µM of indole-acetic acid (IAA) were identified in wheat leaves by transcriptome analysis. Phylogenetic analysis indicated that the 32 auxin-responsive TabZIPs were classified into eight groups with possible different functions. Phenotypic analysis demonstrated that knocking out the homologous gene of the most down-regulated auxin-responsive TabZIP6D_20 in Arabidopsis (AtHY5) decreased its sensitivity to 1 and 50 µM IAA, while the TabZIP6D_20/hy5 complementary lines recovered its sensitivity to auxin as a wild type (Wassilewskija), suggesting that the down-regulated TabZIP6D_20 was a negative factor in the auxin-signaling pathway. These results demonstrated that the auxin-responsive TabZIP genes might have various and vital functions in the architecture of a wheat leaf under auxin response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Triticum/metabolismo , Filogenia , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Molecules ; 28(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37110692

RESUMO

Silicon-based composites are promising candidates as the next-generation anode materials for high-performance lithium-ion batteries (LIBs) due to their high theoretical specific capacity, abundant reserves, and reliable security. However, expensive raw materials and complicated preparation processes give silicon carbon anode a high price and poor batch stability, which become a stumbling block to its large-scale practical application. In this work, a novel ball milling-catalytic pyrolysis method is developed to fabricate a silicon nanosheet@amorphous carbon/N-doped graphene (Si-NSs@C/NG) composite with cheap high-purity micron-size silica powder and melamine as raw materials. Through systematic characterizations such as XRD, Raman, SEM, TEM and XPS, the formation process of NG and a Si-NSs@C/NG composite is graphically demonstrated. Si-NSs@C is uniformly intercalated between NG nanosheets, and these two kinds of two-dimensional (2D) materials are combined in a surface-to-surface manner, which immensely buffers the stress changes caused by volume expansion and contraction of Si-NSs. Attributed to the excellent electrical conductivity of graphene layer and the coating layer, the initial reversible specific capacity of Si-NSs@C/NG is 807.9 mAh g-1 at 200 mA g-1, with a capacity retention rate of 81% in 120 cycles, exhibiting great potential for application as an anode material for LIBs. More importantly, the simple and effective process and cheap precursors could greatly reduce the production cost and promote the commercialization of silicon/carbon composites.

8.
Bioorg Chem ; 129: 106120, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36108587

RESUMO

The purpose of this study was to evaluate the effect of GP inhibitor as a potential pharmaceutical target on MI/R injury. Four different structural types of novel compounds (I, II, III, and IV) were designed and synthesized, obtaining 31 novel GP inhibitors. SAR studies revealed that the conjugates of 5-chloroindole with benzo six-membered heterocyclic were found to elevate the activity. In particular, compound IIIh (IC50 = 0.21 ± 0.03 µM) emerged as a potent derivative against RMGPa, being approximately 2-fold less potent than that of PSN-357. In order to screen out a compound for in vivo activity test, we further conducted an experiment of inhibition against three different subtypes of GPa (HLGPa, HMGPa and HBGPa) and the corresponding affinity experiment. As a result, compound IIIh showed strong inhibitory activity against the above three subtypes of GP, especially on HBGPa (IC50 = 0.09 ± 0.002 µM), which was relatively close to that of positive control ingliforib (IC50 = 0.16 ± 0.02 µM). The affinity of compound IIIh to HBGPa was 4.3 times higher than that of HLGPa, and 1.1 times higher than that of HMGPa. This fact further proved that compound IIIh has a higher inhibitory effect on HMGPa than the other two subtypes. Besides, in vivo activity evaluation demonstrated that compound IIIh exhibited obviously cardioprotective effect on MI/R injury mice. The discovery of compound IIIh provides a new strategy for developing novel GP inhibitors with myocardial ischemia protection.


Assuntos
Inibidores Enzimáticos , Glicogênio Fosforilase , Camundongos , Animais , Relação Estrutura-Atividade , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química
9.
Biochem Biophys Res Commun ; 501(3): 654-660, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29758199

RESUMO

Platelet-activating factor acetylhydrolase IB subunit beta (PAFAH1B2) plays important roles in inflammation and anaphylaxis. However, its primary function in pancreatic cancer remains unclear. In the current study, we report that PAFAH1B2 is overexpressed in pancreatic ductal adenocarcinoma (PDAC) and correlated inversely with patient survival. PAFAH1B2 overexpression induced epithelial-mesenchymal transition (EMT), migration and invasion in vitro and metastasis in vivo. Conversely, silencing PAFAH1B2 inhibited these aggressive phenotypes. Moreover, PAFAH1B2 overexpression in PDAC cells was directly mediated by HIF1a. PAFAH1B2 expression in PDAC clinical specimens correlated positively with HIF1a expression. Overall, our results defined PAFAH1B2 as a target gene of HIF1a and a critical driver of PDAC metastatic behaviors.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas Associadas aos Microtúbulos/genética , Invasividade Neoplásica/genética , Neoplasias Pancreáticas/genética , Idoso , Animais , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Regulação para Cima
10.
Chemistry ; 20(5): 1332-40, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24458913

RESUMO

A mild, convenient, and step-economical intramolecular aminotrifluoromethylation of unactivated alkenes with a variety of electronically distinct, nitrogen-based nucleophiles in the presence of a simple copper salt catalyst, in the absence of extra ligands, is described. Many different nitrogen-based nucleophiles (e.g., basic primary aliphatic and aromatic amines, sulfonamides, carbamates, and ureas) can be employed in this new aminotrifluoromethylation reaction. The aminotrifluoromethylation process allows straightforward access to diversely substituted CF3-containing pyrrolidines or indolines, in good to excellent yields, through a direct difunctionalization strategy from the respective acyclic starting materials. Mechanistic studies were conducted and a plausible mechanism was proposed.


Assuntos
Alcenos/química , Cobre/química , Nitrogênio/química , Catálise , Indóis/química , Metilação , Pirrolidinas/química , Sulfonamidas/química
11.
Oncol Lett ; 27(3): 100, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38298431

RESUMO

[This retracts the article DOI: 10.3892/ol.2018.8999.].

12.
Dalton Trans ; 53(18): 8033-8040, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38651998

RESUMO

We propose a structurally simple, innovative, and multifunctional mid-infrared broadband thermally tunable metamaterial absorption device. The absorption device consists of a three-layer structure, from bottom to top: Ti substrate, SiO2 dielectric layer, and patterned VO2 layer. Through temperature control, the average absorption intensity of the absorption device can vary between 0.08 and 0.94. The absorption device's absorption mechanism is rooted in the thermal phase-change characteristics exhibited by the topologically patterned VO2. When the temperature is below 340 K, VO2 is in a dielectric state, resulting in near-total reflection performance in the mid-infrared range. When the temperature is above 340 K, VO2 undergoes a dielectric-to-metal transition, enabling the absorption device to achieve an average absorption rate of 94.12% in the ultra-wideband range of 6.26 µm-20.96 µm in the mid-infrared. This absorption range completely covers the atmospheric window wavelengths of 8 µm-14 µm, demonstrating high practical value. We explain the working mechanism of the absorption device from the perspective of the electromagnetic field. Subsequently, we study the variations in the absorption curve of the absorption device at different temperatures of VO2 and use the changes in the electric field at the same wavelength under different temperatures to explain the variations in absorption. Compared to previous work, our structure has only three layers in a single unit, making it easy to process and produce. Additionally, the absorption device's operating bandwidth and average absorption rate in the mid-infrared range have been significantly improved. Furthermore, the absorption device exhibits substantial incident angle tolerance and polarization insensitivity. We believe that this design has broad application potential in future optothermal conversion, infrared stealth, and thermal radiation.

13.
Neural Netw ; 179: 106594, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39121788

RESUMO

This work addresses the challenge of democratizing advanced Large Language Models (LLMs) by compressing their mathematical reasoning capabilities into sub-billion parameter Small Language Models (SLMs) without compromising performance. We introduce Equation-of-Thought Distillation (EoTD), a novel technique that encapsulates the reasoning process into equation-based representations to construct an EoTD dataset for fine-tuning SLMs. Additionally, we propose the Ensemble Thoughts Distillation (ETD) framework to enhance the reasoning performance of SLMs. This involves creating a reasoning dataset with multiple thought processes, including Chain-of-Thought (CoT), Program-of-Thought (PoT), and Equation-of-Thought (EoT), and using it for fine-tuning. Our experimental performance demonstrates that EoTD significantly boosts the reasoning abilities of SLMs, while ETD enables these models to achieve state-of-the-art reasoning performance.


Assuntos
Idioma , Humanos , Pensamento/fisiologia , Redes Neurais de Computação , Modelos Teóricos , Matemática
14.
Front Med (Lausanne) ; 11: 1399744, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933104

RESUMO

Intestinal ischemia/reperfusion is a prevalent pathological process that can result in intestinal dysfunction, bacterial translocation, energy metabolism disturbances, and subsequent harm to distal tissues and organs via the circulatory system. Acute lung injury frequently arises as a complication of intestinal ischemia/reperfusion, exhibiting early onset and a grim prognosis. Without appropriate preventative measures and efficacious interventions, this condition may progress to acute respiratory distress syndrome and elevate mortality rates. Nonetheless, the precise mechanisms and efficacious treatments remain elusive. This paper synthesizes recent research models and pertinent injury evaluation criteria within the realm of acute lung injury induced by intestinal ischemia/reperfusion. The objective is to investigate the roles of pathophysiological mechanisms like oxidative stress, inflammatory response, apoptosis, ferroptosis, and pyroptosis; and to assess the strengths and limitations of current therapeutic approaches for acute lung injury stemming from intestinal ischemia/reperfusion. The goal is to elucidate potential targets for enhancing recovery rates, identify suitable treatment modalities, and offer insights for translating fundamental research into clinical applications.

15.
Eur J Pharmacol ; 963: 176219, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38040079

RESUMO

Sepsis-associated lung injury often coexists with intestinal dysfunction. Butyrate, an essential gut microbiota metabolite, participates in gut-lung crosstalk and has immunoregulatory effects. This study aims to investigate the effect and mechanism of sodium butyrate (NaB) on lung injury. Sepsis-associated lung injury was established in mice by cecal ligation and puncture (CLP). Mice in treatment groups received NaB gavage after surgery. The survival rate, the oxygenation index and the lung wet-to-dry weight (W/D) ratio were calculated respectively. Pulmonary and intestinal histologic changes were observed. The total protein concentration in bronchoalveolar lavage fluid (BALF) was measured, and inflammatory factors in serum and BALF were examined. Diamine oxidase (DAO), lipopolysaccharide (LPS), and surfactant-associated protein D (SP-D) levels in serum and amphiregulin in lung tissue were assessed. Intercellular junction protein expression in the lung and intestinal tissues were examined. Changes in immune cells were analyzed. NaB treatment improved the survival rate, the oxygenation index and the histologic changes. NaB decreased the W/D ratio, total protein concentration, and the levels of proinflammatory cytokines, as well as SP-D, DAO and LPS, while increased the levels of anti-inflammatory cytokines and amphiregulin. The intercellular junction protein expression were improved by NaB. Furthermore, the CD4+/CD8+ T-cell ratio and the proportion of CD4+Foxp3+ regulatory T cells (Tregs) were increased by NaB. Our data suggested that NaB gavage effectively improved the survival rate and mitigated lung injury in CLP mice. The possible mechanism was that NaB augmented CD4+Foxp3+ Tregs and enhanced the barrier function of the gut and the lung.


Assuntos
Lesão Pulmonar Aguda , Sepse , Camundongos , Animais , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/complicações , Ácido Butírico/farmacologia , Ácido Butírico/uso terapêutico , Ácido Butírico/metabolismo , Anfirregulina/metabolismo , Linfócitos T Reguladores/metabolismo , Lipopolissacarídeos/metabolismo , Proteína D Associada a Surfactante Pulmonar/metabolismo , Pulmão/patologia , Citocinas/metabolismo , Fatores de Transcrição/metabolismo , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/metabolismo , Fatores de Transcrição Forkhead/metabolismo
16.
Dalton Trans ; 53(25): 10618-10625, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38857028

RESUMO

Utilizing the phase transition principle of VO2, this paper presents a tunable ultra-wideband terahertz perfect absorption device with simple structure and tunability. The proposed broadband terahertz perfect absorption device is a three-layer structure with a metal reflective layer, a silicon dioxide dielectric layer and a VO2 layer from bottom to top. It was found that the terahertz perfect absorption device's absorption could be dynamically adjusted from 1.2% to 99.9% when changing from an insulated to a metallic state. With the VO2 in the metallic state, the terahertz perfect absorption device has an absorption efficiency of more than 90% in 4.00 to 10.08 THz's ultra-broadband range and near-perfect absorption is achieved in the ranges of 4.71 THz to 5.16 THz and 7.74 THz to 8.06 THz. To explain the working principle of this terahertz perfect absorption device, this paper utilizes wave interference's principle, theory of impedance matching and electric field analysis. Compared to previously reported terahertz metamaterial devices, the vanadium dioxide device proposed in this paper is significantly optimized in terms of tunable range and absorption bandwidth. In addition, the terahertz perfect absorption device is polarization insensitive and maintains good absorptivity over a wide-angle incidence range. This tunable ultra-wideband terahertz perfect absorption device could have applications in the fields of modulation, stealth devices, and thermal emission devices.

17.
Dalton Trans ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373786

RESUMO

Metamaterial absorbers show great potential in many scientific and technological applications by virtue of their sub-wavelength and easy-to-adjust structure, with bandwidth as an important standard to measure the performance of the absorbers. In this study, our team designed a new broadband absorber, which consists of an indium arsenide (InAs) disk at the top, a zinc selenide (ZnSe)-chromium (Cr) stacked disk in the middle and a metal film at the bottom. Simulation results show that the absorber has remarkable absorptivity properties in the mid-long infrared band. In a wavelength range of 5.71-16.01 µm, the average absorptivity is higher than 90%. In the band of 5.86-15.49 µm, the absorptivity is higher than 95%. By simulating the electromagnetic field diagram at each resonant frequency, the reason for high broadband absorptivity is obtained. We also constructed Poynting vector diagrams to further elucidate this phenomenon. Next, we analyzed the influence of different materials and structural parameters on absorptivity properties and tested spectral response at different polarization angles and oblique incidence of the light source in the TM and TE modes. When the source is normally incident, the absorber shows polarization insensitivity. When the angle is 40°, absorptivity is still high, indicating that the absorber also possesses angle insensitivity. The broadband absorber proposed by us has good prospects in infrared detection and thermal radiators.

18.
Mol Neurobiol ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39322832

RESUMO

People with type 1 diabetes (T1D) have a significantly elevated risk of stroke, but the mechanism through which T1D worsens ischemic stroke remains unclear. This study was aimed at investigating the roles of T1D-associated changes in the gut microbiota in aggravating ischemic stroke and the underlying mechanism. Fecal 16SrRNA sequencing indicated that T1D mice and mice with transplantation of T1D mouse gut microbiota had lower relative abundance of butyric acid producers, f_Erysipelotrichaceae and g_Allobaculum, and lower content of butyric acid in feces. After middle cerebral artery occlusion (MCAO), these mice had poorer neurological outcomes and more severe inflammation, but higher expression of myeloid differentiation factor 88 (MyD88) in the ischemic penumbra; moreover, the microglia were inclined to polarize toward the pro-inflammatory type. Administration of butyrate to T1D mice in the drinking water alleviated the neurological damage after MCAO. Butyrate influenced the response and polarization of BV2 and decreased the production of inflammatory cytokines via MyD88 after oxygen-glucose deprivation/reoxygenation. Knocking down MyD88 in the brain alleviated neurological outcomes and decreased the concentrations of inflammatory cytokines in the brain after stroke in mice with transplantation of T1D mouse gut microbiota. Poor neurological outcomes and aggravated inflammatory responses of T1D mice after ischemic stroke may be partly due to differences in microglial polarization mediated by the gut microbiota-butyrate-MyD88 pathway. These findings provide new ideas and potential intervention targets for alleviating neurological damage after ischemic stroke in T1D.

19.
Dalton Trans ; 53(29): 12098-12106, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38973455

RESUMO

In this paper, a broadband solar absorber is constructed and simulated based on the finite difference time domain method (FDTD). The modeled structure of the absorber consists of cyclic stacking of five absorber cells with different periods on refractory metal W, where a single absorber cell is composed of a three-layer SiO2-InAs-TiN square film. Due to the Fabry-Perot resonance and the surface plasmon resonance (SPR), an absorptivity greater than 90% within a bandwidth of 2599.5 nm was achieved for the absorber. Notably, one of these bands, 2001 nm, is a high-efficiency absorption with an absorption rate greater than 99%. The average absorption efficiency reaches 99.31% at an air mass of 1.5 (AM 1.5), and the thermal radiation efficiencies are 97.35% and 97.83% at 1000 K and 1200 K, respectively. At the same time, the structure of the absorber is also polarization-independent, and when the solar incidence angle is increased to 60°, it still achieves an average absorption of 90.83% over the entire wavelength band (280 nm to 3000 nm). The novelty of our work is to provide a design idea based on a unit structure with multiple cycles, which can effectively expand the absorption bandwidth of the absorber in the visible-near-infrared wavelengths. The excellent performances make the structure widely used in the field of solar energy absorption.

20.
Artigo em Zh | MEDLINE | ID: mdl-22931872

RESUMO

OBJECTIVE: To evaluate the therapeutic effects of epidermal growth factor (EGF) combined with plasma cryoprecipitate (CRYO) on the corneal injury induced by paraquat (PQ). METHODS: According to the "Toxicological test methods of pesticides for registration" (GB 15670-1995), the conjunctival sacs of 18 health New Zealand rabbits were exposed to 100 µl 20% PQ, which were randomly divided into EGF, CRYO and EGF plus CRYO groups. The routine treatments (normal saline washing and antibiotic eyedrops) were administrated to the injured eyes of 3 groups, at the same time the left eyes of 3 groups were treated with EGF, CRYO and EGF plus CRYO, respectively. The injury of conjunctival, iris and corneal, fluorescent stranded and pathology changes of corneal were observed. The injury score was calculated and the recovery time of corneal injury was recorded. RESULTS: The recovery time of corneal injury in EGF and EGF plus CRYO groups were 19.50 ± 3.08 and 18.67 ± 2.73 days, respectively which were significantly lower than those (27.33 ± 2.58 and 26.83 ± 3.13 days) in corresponding routine treatment controls (P < 0.05). CONCLUSION: EGF and EGF plus CRYO could be used to treat the corneal injury induced by paraquat.


Assuntos
Córnea/efeitos dos fármacos , Fator de Crescimento Epidérmico/uso terapêutico , Traumatismos Oculares/tratamento farmacológico , Fator VIII/uso terapêutico , Fibrinogênio/uso terapêutico , Cicatrização/efeitos dos fármacos , Animais , Transfusão de Sangue Autóloga , Lesões da Córnea , Traumatismos Oculares/induzido quimicamente , Soluções Oftálmicas , Paraquat/efeitos adversos , Plasma , Coelhos , Resultado do Tratamento
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