Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
2.
Sci Rep ; 14(1): 9317, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653748

RESUMO

Carbon fibre-reinforced polymer (CFRP) plates can efficiently repair or enhance the mechanical properties of the square hollow section. However, the loading end of such a CFRP-strengthened member is prone to local bearing failure under compressive load. Given this limitation, an innovative CFRP-plate-strengthened square hollow section composite member (CFRP-SHSCM) was raised, and the thick-walled section was welded on both ends of the thin-walled steel column. The mechanical properties of CFRP-SHSCMs were investigated through parameter finite element (FE) analysis, focusing on the influence of the amount of CFRP layers (nc), the slenderness ratio (λ), the initial geometric imperfections (v0), the CFRP layouts (2S and 4S) and the length of the exposed steel column (Le). The load-displacement curves, the bearing force, and typical failure modes were also acquired. Results indicated that with increasing nc and v0, and decreasing λ, the conventional CFRP-SHSCMs were prone to local bearing failure with poor ductility, leading to the insufficient use of the CFRP plate, in contrast, the improved CFRP-SHSCMs primarily underwent overall buckling failure and exhibited better bearing force and ductility. Finally, the modified Perry-Robertson formula was put forward to predict the ultimate load of the CFRP-SHSCMs. The coefficients of variation between the FE simulation and the theoretical results were 0.00436 and 0.0292, respectively.

3.
Brain Res Bull ; 203: 110772, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37793596

RESUMO

BACKGROUND: Rhizoma Gastrodiae is a highly valuable traditional Chinese medicine and functional health food that has been used in China to treat neurological disorders for thousands of years. Rhizoma Gastrodiae contains various of biological activities, such as antioxidative, neuroprotective, learning improvement, anxiolytic, and antidepressant effects. However, no studies have been conducted to explore the effects of the protein components in Rhizoma Gastrodiae (GEPS) and its potential protective effects against ischemic stroke.Our main goal was to investigate the effects of GEPS on ischemia/reperfusion (I/R) injury and its possible mechanisms. METHODS: A middle cerebral artery occlusion (MCAO) induced focal cerebral ischemia mouse model and an oxygen-glucose deprivation (OGD/R) injury model in HT22 cells were established. A neurobehavioral test was performed 24 h after MCAO, and brain infarction was measured. A Morris water maze experiment was conducted on Day 14 after reperfusion in mice. Hematoxylin and eosin (HE) and TUNEL staining were performed to assess apoptotic neuronal death. Immunohistochemical analysis was used to detect BDNF and GAP43 expression. The content of SOD, MDA, GSH-PX and ROS were detected. The protein expression was analyzed using Western blotting. Cell viability was determined by MTT assay. Cell apoptosis was examined by flow cytometry. RESULTS: GEPS reduced apoptosis, decreased cerebral infarction, improved neurological defects, and ameliorated oxidative stress in the ischemic penumbra. In addition, GEPS increased the expression of BDNF and GA43 in the penumbra. Mechanistically, GEPS counteracted MCAO-induced PI3K/AKT inhibition and activation of MAPK signaling pathways. CONCLUSION: GEPS has a clear neuroprotective effect on I/R injury, and its mechanism may be linked to the PI3K/AKT and MAPK signaling pathways.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos Sprague-Dawley , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transdução de Sinais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Fármacos Neuroprotetores/farmacologia , Apoptose
4.
Front Pharmacol ; 14: 1092693, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033659

RESUMO

Rhizoma Gastrodia (Orchidaceae; Gastrodia elata Blume), the rhizome of Gastrodia elata Blume (GE), is traditionally used as both a medicinal and functional food, with proven efficacy in treating mental disorders. In traditional processing, GE is washed, steamed with water, dried, and sliced. In this study, a novel processing technology-alcohol steamed GE (AGE) was proposed as an alternative. Totally, 17 compounds were identified in fresh GE and AGE. Compared with fresh GE, the relative content of parishin A and parishin E decreased after alcohol steaming, whereas gastrodin (GAS), p-hydroxylbenzyl alcohol (HBA), Parishin B, and Parishin C were increased. Additionally, the pentobarbital-induced sleep mice model and Chronic Restraint Stress (CRS) model were applied to evaluate the pharmacological effects of fresh GE and steamed GE, and both fresh and steamed GE showed an intensive hypnotic and anti-anxiety effect. Furthermore, the anti-anxiety mechanism based on serum metabolic was investigated and the tryptophan metabolic pathway was considered the response to the anti-anxiety effect of GE. Although the optimization of the processing technology of AGE still needs to be further explored, the current results have provided new thoughts for the processing technology and clinical application of GE.

5.
Materials (Basel) ; 15(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35591616

RESUMO

In this paper, we show the influence of stone powder content on the mechanical properties of concrete by experiments and numerical simulations. In numerical simulation, this paper proposed a method whereby the stone powder in the numerical simulation of concrete is considered by the mechanical performances of mortar with the stone powder. The results of numerical models established based on inclusion theory and random aggregate distribution were basically consistent with the experiment, which indicated that the simulation method of concrete under different stone powder was feasible. In the range of stone powder content from 0% to 15%, the model based on inclusion theory is very close to the experimental results, and the model based on 2D random aggregate distribution is closer to the experimental value once the stone powder content is 7%. The research showed that with increased stone powder, cubic compressive strength had greater dispersion between the simulation and the experiment; axial compressive and split tensile strength reached the best levels at 5%. The best stone powder content was 5% for C80 high-strength concrete by comprehensively considering concrete's consistency and its mechanical properties.

6.
Front Pharmacol ; 12: 646239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912056

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and it has gradually become the main disease burden in the world. However, the pathogenesis of NAFLD is complex, involving such things as dyslipidemia, oxidative stress, inflammation, etc. This brings to the table a significant challenge for drug development, and there is still no drug approved by the FDA on the market to treat the disease. GAS and HBA are active ingredients of the orchidaceae plant gastrodia elata and have exhibit effects in ameliorating nervous system diseases caused by oxidative stress. HBA is a metabolite of GAS that could perform lipid regulation and improve oxidative stress on HCD-induced NAFLD larval zebrafish, as reported by previous studies; we therefore explored the role of HBA in lipid regulation and oxidative stress on HCD-induced NAFLD larval zebrafish in vivo and FFA-induced BRL-3A hepatocyte in vitro. The gene expression of lipogenesis, inflammation, and oxidative stress were measured to investigate the underlying mechanism of HBA, and the potential protein target of HBA was explored by immunofluorescence. Altogether, our data highlight the role of HBA in improving NAFLD by use of its lipid-lowering and anti-oxidative properties via the Nrf2/HO-1 signaling pathway, providing a potential therapeutic compound for NAFLD treatment.

7.
ACS Appl Mater Interfaces ; 12(38): 43311-43319, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32870645

RESUMO

Heterojunctioned transition-metal dichalcogenide (TMD) films with regulatable interface adhesion have shown broad application prospects in the design of advanced materials and the manufacturing of novel functional devices. To date, the controlled fabrication of TMD heterojunctions or heterojunction-rich films with tailorable thickness and composition has proved challenging. Herein, a bimetallic co-feeding atomic layer deposition (ALD) system was developed capable of fulfilling these requirements. In the co-feeding ALD fabrication, by adjusting the Re/Mo ratio, 3-layered quasibinary heterojunctioned ReS2/MoS2 films with adjustable composition and grain size were prepared. Moreover, the measurements between atomic force microscopy Si tip coated with the ReS2/MoS2 films and films on the substrate indicate that the adhesion force can be regulated from 13.5 to 136.3 nN. Further experimental data and theoretical analysis show that the adhesion force between the coated tip and films possesses a positive correlation with the "tip-film unanimity" in composition.

8.
Small ; 16(28): e2001223, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32529739

RESUMO

Artificial photoresponsive nanochannels have attracted widespread attention because of their capacity to achieve ion transport through light modulation. Herein, a biosensor for ultrasensitive miRNA-155 detection is devised based on molybdenum disulfide (MoS2 ) modified porous anodic aluminum oxide (AAO) photoresponsive nanochannels by atomic layer deposition (ALD). According to the optimized experimental results, when the cycles of ALD, the wavelength, and the power of the excitation laser are 70 cycles, 450 nm, and 80 mW, respectively, the most supreme photocurrent performance of these photoresponsive nanochannels are obtained. AAO nanochannels modified with MoS2 can work as a photoelectrochemical (PEC) biosensor by generating photoexcitation current; what is more, the high channel density in AAO can magnify the ion current signal response effectively by aggrandizing the flux of electroactive species. By using AAO photoresponsive nanochannels with an average diameter of 150 nm as PEC biosensor, an ultrasensitive detection record ranging from 0.01 fM to 0.01 nM with a detection limit of 3 aM can be achieved. This work not only proposes a simple method for manufacturing semiconductor photoresponsive nanochannels, but also exhibits great potential in the ultrasensitive detection of biomolecules.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Óxido de Alumínio , Dissulfetos , Limite de Detecção , Molibdênio , Porosidade
9.
ACS Appl Mater Interfaces ; 12(26): 29074-29084, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492335

RESUMO

Rhenium disulfide (ReS2), which possessed a unique direct band gap from the bulk to monolayer, played a very important role in establishing optoelectronic devices, while the rapid recombination of electron-hole pairs might hinder its further applications. Therefore, to improve its photocurrent performance, a bimetallic co-chamber feeding atomic layer deposition (ALD) with a precise dose regulation strategy was used to fabricate MoS2-ReS2 heterojunctions with a controllable Mo-to-Re ratio in this work. Furthermore, because of the controlled addition of Mo atoms, the electron-transfer capacity, carrier mobility, and photocurrent response of these heterojunctions were significantly improved among which the sample obtained under 100 supercycles (one supercycle for this sample consists of the following in turn: one ReCl5 pulse, one H2S pulse, one ReCl5 pulse, one MoCl5 pulse, and one H2S pulse; the real Mo-to-Re ratio Rr = 57.9%) exhibited the best photocurrent response. Due to the significant improvement in optoelectronic performance, a photoelectrochemical (PEC) biosensor with the basis of the above optimized sample could achieve the ultrasensitive detection of cancer-related miRNA-21 ranging from 10 aM to 1 nM with a low detection limit of 2.8 aM.

10.
Int J Mol Sci ; 20(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018538

RESUMO

Non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) is the most common chronic liver disease in the world. However, there are still no drugs for NAFLD/NASH in the market. Gastrodin (GAS) is a bioactive compound that is extracted from Gastrodia elata, which is used as an active compound on nervous system diseases. Recent reports showed that GAS and Gastrodia elata possess anti-oxidant activity and lipid regulating effects, which makes us curious to reveal the anti-NAFLD effect of GAS. A high cholesterol diet (HCD) was used to induce a NAFLD larval zebrafish model, and the lipid regulation and anti-oxidant effects were tested on the model. Furthermore, qRT-PCR studied the underlying mechanism of GAS. To conclude, this study revealed a lipid regulation and anti-oxidant insights of GAS on NAFLD larval zebrafish model and provided a potential therapeutic compound for NAFLD treatment.


Assuntos
Antioxidantes/uso terapêutico , Álcoois Benzílicos/uso terapêutico , Gastrodia/química , Glucosídeos/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Antioxidantes/isolamento & purificação , Álcoois Benzílicos/isolamento & purificação , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/isolamento & purificação , Larva/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA