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1.
Psychophysiology ; : e14675, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218953

RESUMO

Peer presence influences risk-taking behavior, particularly in adolescence. Based on the dual system model, this event-related potential study examined whether and how the presence of a peer displayed a preference for risky behavior would increase adolescents' risk-taking by disrupting their cognitive control processes in either emotional or non-emotional contexts. A sample of 106 adolescents (17-19 years of age) completed two Stoop tasks and a Balloon Analog Risk Task under three peer presence conditions. Results revealed that compared to other conditions, the presence of a risk-averse peer caused adolescents to make safer decisions through improving their conflict monitoring (more negative N200-diff), whereas a risk-preference peer's presence led adolescents to more risky decisions through disrupting their conflict resolution (more positive N450-diff) but they were only observed on the Emotional Stroop task. These findings suggest that different peer presence contexts could increase or decrease adolescents' risk-taking behaviors by influencing their cognitive control under an emotional context rather than in a non-emotional context.

2.
Macromol Rapid Commun ; : e2400576, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283835

RESUMO

Skinless, hierarchical porous 3D polymer scaffolds are of critical importance in tissue engineering, enabling improved cell infiltration, nutrient, metabolite and energy exchange, and biomimetic structures, crucial for regenerative medicine, drug delivery, and advanced material applications. However, it is still a great challenge to construct this kind of material with traditional 3D printing techniques. Herein, a novel simple, and versatile in situ precipitation-assisted direct-write-3D printing strategy for skinless, hierarchical porous 3D scaffolds is reported. Homogenous ink containing molecularly dissolved fructose (soluble porogen molecule) and polymer (whether it is hydrophilic, hydrophobic or amphiphilic) is directly extruded into a nonsolvent bath, where simultaneously solidification of the polymer and in situ precipitation of the porogen molecules both on the exterior surface and inside the separated polymer fibers happen. Subsequently, by simply leaching the in situ formed porogen particles, skinless hierarchical porous polymeric 3D scaffolds can be obtained. It is believed that 3D printing, polymer/macromolecule-based scaffolds, especially the skinless hierarchical porous biomaterials, and the tissue engineering market can benefit tremendously from this simple and versatile approach.

3.
Pestic Biochem Physiol ; 199: 105774, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458681

RESUMO

Aphis gossypii, a globally distributed and economically significant pest of several crops, is known to infest a wide range of host plants. Heat shock proteins (Hsps), acting as molecular chaperones, are essential for the insect's environmental stress responses. The present study investigated the molecular characteristics and expression patterns of AgHsp70, a heat shock protein gene, in Aphis gossypii. Our phylogenetic analysis revealed that AgHsp70 shared high similarity with homologs from other insects, suggesting a conserved function across species. The developmental expression profiles of AgHsp70 in A. gossypii showed that the highest transcript levels were observed in the fourth instar nymphs, while the lowest levels were detected in the third instar nymphs. Heat stress and exposure to four different xenobiotics (2-tridecanone, tannic acid, gossypol, and flupyradifurone (4-[(2,2-difluoroethyl)amino]-2(5H)-furanone)) significantly up-regulated AgHsp70 expression. Knockdown of AgHsp70 using RNAi obviously increased the susceptibility of cotton aphids to 2-tridecanone, gossypol and flupyradifurone. Dual-luciferase reporter assays revealed that gossypol and flupyradifurone significantly enhanced the promoter activity of AgHsp70 at a concentration of 10 mg/L. Furthermore, we identified the transcription factor heat shock factor (HSF) as a regulator of AgHsp70, as silencing AgHSF reduced AgHsp70 expression. Our results shed light on the role of AgHsp70 in xenobiotic adaptation and thermo-tolerance.


Assuntos
4-Butirolactona/análogos & derivados , Afídeos , Gossipol , Cetonas , Polifenóis , Piridinas , Animais , Afídeos/genética , Afídeos/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Gossipol/metabolismo , Filogenia , Xenobióticos/farmacologia , Xenobióticos/metabolismo
4.
Sensors (Basel) ; 24(14)2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39066131

RESUMO

This work presents TTFDNet, a transformer-based and transfer learning network for end-to-end depth estimation from single-frame fringe patterns in fringe projection profilometry. TTFDNet features a precise contour and coarse depth (PCCD) pre-processor, a global multi-dimensional fusion (GMDF) module and a progressive depth extractor (PDE). It utilizes transfer learning through fringe structure consistency evaluation (FSCE) to leverage the transformer's benefits even on a small dataset. Tested on 208 scenes, the model achieved a mean absolute error (MAE) of 0.00372 mm, outperforming Unet (0.03458 mm) models, PDE (0.01063 mm) and PCTNet (0.00518 mm). It demonstrated precise measurement capabilities with deviations of ~90 µm for a 25.4 mm radius ball and ~6 µm for a 20 mm thick metal part. Additionally, TTFDNet showed excellent generalization and robustness in dynamic reconstruction and varied imaging conditions, making it appropriate for practical applications in manufacturing, automation and computer vision.

5.
Molecules ; 28(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687116

RESUMO

Hericium erinaceus (HE), a widely utilized natural remedy and dietary source, has garnered significant attention for its therapeutic potential in various diseases. In this study, we employed supercritical fluid extraction (SFE) technology to isolate the bioactive compounds from HE's fruiting body. Comprehensive assessments of the antioxidant and antibacterial activities were conducted, along with in vitro investigations on the human colon cancer cell line (HCT-8). The SFE rate served as the evaluation metric, while the variables of extraction time, pressure, and temperature were systematically examined. By integrating the response surface center composite design, we successfully optimized the extraction process, yielding optimal parameters of 80 min, 30 MPa, and 35 °C, thus resulting in an extraction rate of 2.51%. These optimized conditions exhibited considerable antioxidant capacity, anticancer activity, and antibacterial potential. Furthermore, we employed graded alcohol extraction to refine the crude extracts, thereby confirming superior anticancer effects under a 70% alcohol precipitation. To elucidate the composition, Fourier-transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) were employed to analyze the crude extracts and isolates of HE, facilitating a comparative analysis of six HE varieties. Our findings suggest that sterol derivatives hold promise as the active component against the colon cancer HCT-8 cell line. In conclusion, this study underscores the potential of HE SFE in the development of functional foods or alternative drugs for colon cancer treatment, thus opening new avenues for therapeutic interventions.


Assuntos
Neoplasias do Colo , Humanos , Antioxidantes/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Neoplasias do Colo/tratamento farmacológico , Antibacterianos/farmacologia
6.
Biochem Biophys Res Commun ; 627: 84-90, 2022 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-36030656

RESUMO

Proton pump inhibitors (PPIs) are often prescribed in association with clopidogrel and aspirin to patients with myocardial infraction (MI), but their effects on heart is controversial. The purpose of this study was to investigate the effects and potential mechanism of omeprazole (OME) and esomeprazole (ESO) in myocardial ischemia reperfusion (I/R) injury. In the present study, mice were treated with OME, ESO or vehicle for 3 weeks and then subjected to myocardial I/R or sham surgery. At 1 day after surgery, echocardiography was performed to access cardiac injury. Hematoxylin and eosin (H&E) staining was performed to evaluate cardiomyocyte morphology. The IL1ß was evaluated by Immunohistochemistry (IHC). Elisa was used to detect cTnt content in serum. The expression of CD86, CD206, CHOP, ATF6, eIF2α and p eIF2α were determined by Western blot (WB). The result showed that ESO markedly improved the left ventricular ejection fraction (LVEF), shortening fraction (FS), suppressed inflammatory infiltration, endoplasmic reticulum stress (ERS) and decreased proinflammatory macrophages in I/R hearts, while OME had no significant effects on cardiac function, inflammation and ERS in the I/R heart. In conclusion, ESO but not OME pretreatment reduces the proportion of proinflammatory macrophages, inhibits endoplasmic reticulum stress, and alleviates I/R injury in mice, indicating that ESO maybe a more proper PPI than OME for application in I/R injury.


Assuntos
Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Animais , Apoptose , Estresse do Retículo Endoplasmático , Esomeprazol/farmacologia , Esomeprazol/uso terapêutico , Camundongos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Volume Sistólico , Função Ventricular Esquerda
7.
J Youth Adolesc ; 51(11): 2161-2172, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35861907

RESUMO

A number of studies have focused on the same-sex peer effect on and the developmental difference in adolescent risk-taking in terms of the dual systems model. Little research, however, addresses the effects of different observers, the role of different levels of individual self-control, and their interactions. To fill this gap, the present study examined the main and interactive effects of observer presence and individual self-control on male adolescents' risk-taking behavior with an experimental design. A total of 261 male adolescents (Mage = 15.79 ± 0.79, range = 14-18) completed an adapted Stoplight Task, which measures risk-taking behavior, in the presence of an observer, either peer or adult, either male or female. The results indicated that a same-sex peer's presence and low self-control were both risk factors of male adolescents' risk-taking, but did only low self-control male adolescents take serious risks when in the presence of a same-sex peer whereas those with high self-control consistently had low levels of risk-taking under any condition. An opposite-sex observer, particularly an opposite-sex adult's presence, played a similar protective role for male adolescents with low self-control. The findings suggest that a high level of self-control closely related to the cognitive control system may significantly buffer the negative effect of an adverse social stimulus which activates the social-emotional system on male adolescents' risk-taking; the findings also reveal that an opposite-sex adult's presence may contribute to a decrease in male adolescents' risk-taking by improving their cognitive control system.


Assuntos
Comportamento do Adolescente , Autocontrole , Adolescente , Comportamento do Adolescente/psicologia , Adulto , Feminino , Humanos , Masculino , Grupo Associado , Assunção de Riscos , Comportamento Social
8.
J Youth Adolesc ; 49(8): 1674-1686, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32578000

RESUMO

With China's fast-growing economy, family dinners are often overlooked. However, family dinner, as an important routine family activity, provides an opportunity for interaction between adolescents and their parents, which promotes adolescents' happiness. Guided by the positive youth development perspective, the character strength theory of happiness and the family investment model, the current study simultaneously investigated the mediating role of adolescents' internal assets and the moderating role of parental educational level in the influence of family dinner on adolescents' happiness in Chinese families. A three-wave longitudinal study spanning approximately three years was conducted among 817 Chinese seventh graders (52.4% male; Mage = 12.62 years). The frequency of family dinner at the first year was significantly positively correlated with adolescents' happiness in the first and third years. The cross-sectional and longitudinal results showed that adolescents' internal assets mediated the relationship between family dinner frequency and happiness. Specifically, family dinner with higher-educated parents was a stronger predictor of internal assets than family dinner with lower-educated parents after one year. These findings from the Chinese cultural context complement the research in this field and inform practical endeavors to promote adolescents' happiness worldwide based on the strengths of different cultures.


Assuntos
Felicidade , Pais , Adolescente , China , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino
9.
Macromol Rapid Commun ; 40(12): e1900111, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30969013

RESUMO

The helix and superhelix play critical roles in the achievement of tissue functions. These fascinating structures have attracted increasing interest due to their potential biomimicking applications. However, continuous and controlled fabrication of these structures, especially the superhelical structures, from various polymers for different practical applications still remains a big challenge. Here, a novel and versatile microfluidic spinning strategy is presented for generation of both helical and superhelical microfibers from either hydrophilic, hydrophobic, or amphiphilic polymers. The diameter (d ), wavelength (λ), and amplitude (A) of these microfibers could be highly controlled. The helical microfibers show outstanding elongations and potential applications in magnetic responsive elastic microactuators. It is envisioned that these results will greatly enrich the possibility of generating new multiple-ordered structures from various polymers for applications in different areas.


Assuntos
Técnicas Analíticas Microfluídicas , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Substâncias Macromoleculares/química , Tamanho da Partícula , Propriedades de Superfície
10.
J Mater Sci Mater Med ; 30(12): 135, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802280

RESUMO

The major challenge to treat the clinical adverse effects of long-segment urethra is in achieving viable tissue substitution. The substituted construct's properties-such as its resilience, contraction, and ability to minimize scar-stenosis formation should be considered. In the present work, a unique polyurethane-urea (PUU) fibrous membrane is fabricated by electrospinning. Then PUU was coated by collagen and formed the elasticity hydrogel after immersed in collagen solution. Meanwhile, the cPUU hydrogel exhibited a fibrous microstructure. This cPUU hydrogel had outstanding stretching property with 404 ± 40% elongation at break compared with traditional hydrogels, which satisfied the requirement of urethra. The cPUU hydrogel also supported the adhesion and growth of bladder smooth-muscle cells (BSMCs) in natural state cell morphology. Urethral defects in New Zealand male rabbits were repaired with cPUU seeded with BSMCs in vivo. After three months, more smooth-surface area of reconstructed urethral tissues was observed in the cPUU hydrogel-BMSCs groups compared with that of the control group. The luminal patency and the incidence of complications-including calculus formation, urinary fistula, and urethral-stricture occurrence were significantly lower in the cPUU group compared with that of the control group. Hence, cPUU fibrous hydrogels are promising scaffolds for application in urological tissue engineering.


Assuntos
Colágeno/química , Hidrogéis/química , Miócitos de Músculo Liso/fisiologia , Poliuretanos/química , Ureia/química , Doenças Uretrais/terapia , Animais , Materiais Biocompatíveis , Masculino , Teste de Materiais , Coelhos , Engenharia Tecidual , Alicerces Teciduais , Bexiga Urinária/citologia
11.
Molecules ; 24(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027249

RESUMO

Fibrous hydrogel scaffolds have recently attracted increasing attention for tissue engineering applications. While a number of approaches have been proposed for fabricating microfibers, it remains difficult for current methods to produce materials that meet the essential requirements of being simple, flexible and bio-friendly. It is especially challenging to prepare cell-laden microfibers which have different structures to meet the needs of various applications using a simple device. In this study, we developed a facile two-flow microfluidic system, through which cell-laden hydrogel microfibers with various structures could be easily prepared in one step. Aiming to meet different tissue engineering needs, several types of microfibers with different structures, including single-layer, double-layer and hollow microfibers, have been prepared using an alginate-methacrylated gelatin composite hydrogel by merely changing the inner and outer fluids. Cell-laden single-layer microfibers were obtained by subsequently seeding mouse embryonic osteoblast precursor cells (MC3T3-E1) cells on the surface of the as-prepared microfibers. Cell-laden double-layer and hollow microfibers were prepared by directly encapsulating MC3T3-E1 cells or human umbilical vein endothelial cells (HUVECs) in the cores of microfibers upon their fabrication. Prominent proliferation of cells happened in all cell-laden single-layer, double-layer and hollow microfibers, implying potential applications for them in tissue engineering.


Assuntos
Hidrogéis/química , Microfluídica/métodos , Engenharia Tecidual/métodos , Animais , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Camundongos
12.
Chemistry ; 23(69): 17444-17448, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29048136

RESUMO

Patterned surfaces of responsive polymers find applications in diverse fields. However, it is still a great challenge to fabricate hierarchical patterns with long-range orders. Herein controllable hierarchical surface patterns that can be fabricated by combining nanoembossing techniques with the surface instability of supramolecular hydrogels are presented. Nanoembossed nanostripe arrays of polyethylene glycol (PEG)-based polyurethane-urea supramolecular hydrogels are fabricated and exposed to water, whereby the lateral expansion of nanostripes is confined and leads to the formation of folded in-plane or out-of-plane patterns depending on the aspect ratios. The direction of folds is perpendicular to the nanostripes. Both the amplitude and the wavelength of out-of-plane folds are proportional to the thickness of nanostripes. Therefore, hierarchical structures, in which one periodicity is defined by the nanoembossing processes and the other is determined by surface buckling, can be quickly fabricated in supramolecular hydrogel thin films.

13.
Macromol Rapid Commun ; 38(17)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28691355

RESUMO

Strong and tough synthetic hydrogels have received ever-increasing interests due to their potential applications as load-bearing structural materials. However, strong, tough, and recyclable hydrogels in different forms that can be generated by different methods according to various practical applications still remain an intrinsic bottleneck. A simple one-pot synthesis of multiurea linkage segmented linear copolymers with easy recyclability, hybridization, and processability, including compression molding, solution casting, and spinning methods, to yield ultrastrong and tough hydrogel films or stretchable hydrogel fibers with diameters ranged from macro-, micro-, to nanoscale, is reported here.


Assuntos
Técnicas de Química Analítica/métodos , Hidrogéis/síntese química , Polímeros/química , Ureia/química , Hidrogéis/química
14.
Macromol Rapid Commun ; 37(5): 426-32, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26762293

RESUMO

Microfluidic fabrication of helical microfibers is still a big challenge. The reason is that this always includes designing the necessary geometrical channels and chemical conditions to first form a flowing liquid jet, which has to be continually reacting and rapidly evolving in time from viscous liquid to a flexible solid to maintain the helical structure inside the microfluidic channels. In this report, dextran aqueous solution and liquid PEG400 are infused separately into the inner and outer channels of a simple single emulsion microfluidic device, respectively. The formed two phase stream then enters a widening collection tube, where automatically formation of dextran helical fiber happened due to water shifting and widening of the channel cooperatively induced buckling. Various experimental conditions that influence the amplitudes, wavelengths, and diameters of the formed helical fibers are discussed.


Assuntos
Dextranos/química , Microfluídica/métodos , Polietilenoglicóis/química , Dextranos/ultraestrutura , Emulsões , Técnicas Analíticas Microfluídicas , Microfluídica/instrumentação , Viscosidade
15.
J Am Chem Soc ; 136(19): 6969-77, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24803288

RESUMO

Hydrogels were prepared with physical cross-links comprising 2-ureido-4[1H]-pyrimidinone (UPy) hydrogen-bonding units within the backbone of segmented amphiphilic macromolecules having hydrophilic poly(ethylene glycol) (PEG). The bulk materials adopt nanoscopic physical cross-links composed of UPy-UPy dimers embedded in segregated hydrophobic domains dispersed within the PEG matrix as comfirmed by cryo-electron microscopy. The amphiphilic network was swollen with high weight fractions of water (w(H2O) ≈ 0.8) owing to the high PEG weight fraction within the pristine polymers (w(PEG) ≈ 0.9). Two different PEG chain lengths were investigated and illustrate the corresponding consequences of cross-link density on mechanical properties. The resulting hydrogels exhibited high strength and resilience upon deformation, consistent with a microphase separated network, in which the UPy-UPy interactions were adequately shielded within hydrophobic nanoscale pockets that maintain the network despite extensive water content. The cumulative result is a series of tough hydrogels with tunable mechanical properties and tractable synthetic preparation and processing. Furthermore, the melting transition of PEG in the dry polymer was shown to be an effective stimulus for shape memory behavior.


Assuntos
Hidrogéis/química , Polietilenoglicóis/química , Pirimidinonas/química , Reagentes de Ligações Cruzadas/química , Microscopia Crioeletrônica , Dimerização , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Mecânicos , Água/química
16.
ACS Appl Mater Interfaces ; 16(33): 43180-43188, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39110843

RESUMO

The development of bioadhesives with strong adhesion and on-demand adhesion-detachment behavior is still critically important and challenging for facilitating painless and damage-free removal in clinical applications. In this work, for the first time, we report the easy fabrication of novel polyurethane-urea (PUU)-based bioadhesives with thermoresponsive on-demand adhesion and detachment behavior. The PUU copolymer was synthesized by a simple copolymerization of low-molecular-weight, hydrophilic, and biocompatible poly(ethylene glycol), glyceryl monolaurate (GML, a special chain extender with a long side hydrophobic alkyl group), and isophorone diisocyanate (IPDI). Here, GML was expected to not only adjust the temperature-dependent adhesion behavior but also act as an internal plasticizer. By simple adjustment of the water content, the adhesion strength of the 15 wt % water-containing PUU film toward porcine skin is as high as 55 kPa with an adhesion energy of 128 J/m2 at 37 °C. The adhesion strength dramatically decreases to only 3 kPa at 10 °C, exhibiting switching efficiency as high as 0.95. Furthermore, the present PUU-based adhesive also shows good on-demand underwater adhesion and detachment with a cell viability close to 100%. We propose that biomaterial research fields, especially novel PUU/polyurethane (PU)-based functional materials and bioadhesives, could benefit from such a novel thermoresponsive copolymer with outstanding mechanical and functional performances and an easy synthesis and scaled-up process as described in this article.


Assuntos
Poliuretanos , Poliuretanos/química , Poliuretanos/farmacologia , Animais , Suínos , Humanos , Temperatura , Ureia/química , Ureia/farmacologia , Ureia/análogos & derivados , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Adesivos Teciduais/síntese química , Adesão Celular/efeitos dos fármacos , Camundongos , Adesivos/química , Adesivos/farmacologia
17.
Macromol Biosci ; 24(7): e2400047, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38589022

RESUMO

Polyaspartic acid derivatives are a well-known kind of polypeptide with good biocompatibility and biodegradability, and thus have been widely used as biomedical materials, including drug-loaded nano-scale micelles or macroscopic hydrogels. In this work, for the first time, monodisperse polyaspartic acid derivative microspheres with diameter ranging from 120 to 350 µm for potential tumor embolization therapy are successfully prepared by single emulsion droplet microfluidic technique. The obtained microsphere shows fast cationic anticancer drug doxorubicin hydrochloride loading kinetics with high loading capacity, which is much better than those of the commercial ones. Additionally, drug release behaviors of the drug-loaded microspheres with different diameters in different media are also studied and discussed in detail. These results provide some new insights for the preparation and potential application of polyaspartic acid derivative-based monodisperse microspheres, especially for their potential application as embolic agent.


Assuntos
Doxorrubicina , Embolização Terapêutica , Microesferas , Peptídeos , Doxorrubicina/farmacologia , Doxorrubicina/química , Peptídeos/química , Embolização Terapêutica/métodos , Humanos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Liberação Controlada de Fármacos , Tamanho da Partícula , Portadores de Fármacos/química
18.
Heliyon ; 10(7): e29160, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38617915

RESUMO

Dapagliflozin (DAPA) has been demonstrated to reduce cardiovascular mortality and heart failure hospitalization rates in diabetic patients. However, the mechanism underlying its cardio-protective effect in non-diabetic patients remains unclear. Our study aimed to explore the cardio-protective impact of DAPA on myocardial infarction in non-diabetic mice. We induced myocardial infarction in C57BL/6 mice by ligating the descending branch of the left coronary artery. After surgery, the animals were randomly treated with either saline or DAPA. We employed echocardiography, Western blot analysis, and tissue staining to assess post-infarction myocardial injury. Additionally, we investigated the mechanism of action through cell experiments. Compared to the myocardial infarction group, DAPA treatment significantly attenuated ventricular remodeling and improved cardiac function. By mitigating myocardial oxidative stress and apoptosis, DAPA may activate the AMPKα signaling pathway, thereby exerting a protective effect. These findings suggest that DAPA could serve as a novel therapeutic approach for patients with cardiac infarction.

19.
ACS Catal ; 14(1): 406-417, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38205022

RESUMO

The oxygen species on Ag catalysts and reaction mechanisms for ethylene epoxidation and ethylene combustion continue to be debated in the literature despite decades of investigation. Fundamental details of ethylene oxidation by supported Ag/α-Al2O3 catalysts were revealed with the application of high-angle annular dark-field-scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy (HAADF-STEM-EDS), in situ techniques (Raman, UV-vis, X-ray diffraction (XRD), HS-LEIS), chemical probes (C2H4-TPSR and C2H4 + O2-TPSR), and steady-state ethylene oxidation and SSITKA (16O2 → 18O2 switch) studies. The Ag nanoparticles are found to carry a considerable amount of oxygen after the reaction. Density functional theory (DFT) calculations indicate the oxidative reconstructed p(4 × 4)-O-Ag(111) surface is stable relative to metallic Ag(111) under the relevant reaction environment. Multiple configurations of reactive oxygen species are present, and their relevant concentrations depend on treatment conditions. Selective ethylene oxidation to EO proceeds with surface Ag4-O2* species (dioxygen species occupying an oxygen site on a p(4 × 4)-O-Ag(111) surface) only present after strong oxidation of Ag. These experimental findings are strongly supported by the associated DFT calculations. Ethylene epoxidation proceeds via a Langmuir-Hinshelwood mechanism, and ethylene combustion proceeds via combined Langmuir-Hinshelwood (predominant) and Mars-van Krevelen (minor) mechanisms.

20.
Genes Dis ; 11(6): 101074, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39281830

RESUMO

Stimulator of interferon genes (STING) has recently been found to play a crucial role in cardiac sterile inflammation and dysfunction. The role of stimulator of interferon genes (STING) in cardiac sterile inflammation and dysfunction has been recently discovered. This study aims to examine the involvement of STING in pathological cardiac remodeling and the mechanisms that govern the activation of the STING pathway. To investigate this, transverse aortic constriction (TAC) was performed on STING knockout mice to induce pressure overload-induced cardiac remodeling. Subsequently, cardiac function, remodeling, and inflammation levels were evaluated. The STING pathway was found to be activated in the pressure overload-stressed heart and angiotensin II (Ang II)-stimulated cardiac fibroblasts. Loss of STING expression led to a significant reduction in inflammatory responses, mitochondrial fragmentation, and oxidative stress in the heart, resulting in attenuated cardiac remodeling and dysfunction. Furthermore, the exacerbation of pressure overload-induced STING-mediated inflammation and pathological cardiac remodeling was observed when mitophagy was suppressed through the silencing of Parkin, an E3 ubiquitin ligase. Taken together, these findings indicate that STING represents a newly identified and significant molecule implicated in the process of pathological cardiac remodeling and that mitophagy is an upstream mechanism that regulates STING activation. Targeting STING may therefore provide a novel therapeutic strategy for pathological cardiac remodeling and heart failure.

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