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1.
Sci Adv ; 10(32): eado7348, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39110803

RESUMO

Hybrid materials with a rational organic-inorganic configuration can offer multifunctionality and superior properties. This principle is crucial but challenging to be applied in designing the solid electrolyte interphase (SEI) on lithium metal anodes (LMAs), as it substantially affects Li+ transport from the electrolyte to the anode. Here, an artificial SEI with an ultrahigh fluorine content (as high as 70.12 wt %) can be successfully constructed on the LMA using a high-voltage electrosynthesis strategy. This SEI consists of ultrafine lithium fluoride nanocrystals embedded in a fluorinated organic matrix, exhibiting excellent passivation and mechanical strength. Notably, the organic-inorganic interface demonstrates a high dielectric constant that enables fast Li+ transport throughout the SEI. Consequently, LMA coated with this SEI substantially enhances the cyclability of both half-cells and full cells, even under rigorous conditions. This work demonstrates the potential of rationally designed hybrid materials via a unique electrosynthetic approach for advanced electrochemical systems.

2.
BMC Plant Biol ; 24(1): 807, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39187785

RESUMO

Cadmium (Cd) is a biologically non-essential heavy metal, a major soil pollutant, and extremely harmful to plants. The phytohormone methyl jasmonate (MeJA) plays an important role in plant heavy-metal resistance. However, the understanding of the effects of MeJA supply level on alleviating Cd toxicity in plants is limited. Here, we investigated how MeJA regulated the development of physiological processes and cell wall modification in Cosmos bipinnatus. We found that low concentrations of MeJA increased the dry weight of seedlings under 120 µM Cd stress by reducing the transport of Cd from roots to shoots. Moreover, a threshold concentration of exogenous MeJA increased the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in plant roots, the concentration of Cd in the root cell wall, and the contents of pectin and hemicellulose 1 polysaccharides, through converting Cd into pectin-bound forms. These results suggested that MeJA mitigated Cd toxicity by modulating root cell wall polysaccharide and functional group composition, especially through pectin polysaccharides binding to Cd, with effects on Cd transport capacity, specific chemical forms of Cd, and homeostatic antioxidant systems in C. bipinnatus.


Assuntos
Acetatos , Cádmio , Ciclopentanos , Oxilipinas , Reguladores de Crescimento de Plantas , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Acetatos/farmacologia , Cádmio/toxicidade , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Poluentes do Solo/toxicidade , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Antioxidantes/metabolismo , Superóxido Dismutase/metabolismo
3.
Int J Biol Macromol ; 277(Pt 4): 134529, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39111485

RESUMO

Living organisms have developed a miraculous biomineralization strategy to form multistage organic-inorganic composites through the orderly assembly of hard/soft substances, achieving mechanical enhancement of materials from the nanoscale to the macroscale. Inspired by biominerals, this study used polydopamine (PDA) coating as a template to induce the growth of hydroxyapatite (HAP) on the surface of carbon fibers (CFs) for enhancing the interfacial properties of the CF/epoxy resin composites. This polydopamine-assisted hydroxyapatite formation (pHAF) biomimetic mineralization strategy constructs soft/hard ordered structure on the CF surface, which not only improves the chemical reaction activity of the CFs but also increases the fiber surface roughness. This, in turn, enhances the interaction and loading delivery among the fibers and the matrix. Compared to the untreated carbon fiber/epoxy resin (CF/EP) composites, the prepared composites showed a substantial enhancement in interlaminar shear strength (ILSS), flexural strength, and interfacial shear strength (IFSS), with improvements of 45.2 %, 46.9 %, and 60.5 %, respectively. This can be attributed to the HAP nanolayers increasing the adhesion and mechanical interlocking with the CFs to the matrix. This study provides an interface modification method of biomimetic mineralization for the preparation of high strength CF composites.

4.
Materials (Basel) ; 17(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39124317

RESUMO

Additive manufacturing (AM) is a technology that builds parts layer by layer. Over the past decade, metal additive manufacturing (AM) technology has developed rapidly to form a complete industry chain. AM metal parts are employed in a multitude of industries, including biomedical, aerospace, automotive, marine, and offshore. The design of components can be improved to a greater extent than is possible with existing manufacturing processes, which can result in a significant enhancement of performance. Studies on the anisotropy of additively manufactured metallic materials have been reported, and they describe the advantages and disadvantages of preparing different metallic materials using additive manufacturing processes; however, there are few in-depth and comprehensive studies that summarize the microstructural and mechanical properties of different types of additively manufactured metallic materials in the same article. This paper begins by outlining the intricate relationship between the additive manufacturing process, microstructure, and metal properties. It then explains the fundamental principles of powder bed fusion (PBF) and directed energy deposition (DED). It goes on to describe the molten pool and heat-affected zone in the additive manufacturing process and analyzes their effects on the microstructure of the formed parts. Subsequently, the mechanical properties and typical microstructures of additively manufactured titanium alloys, stainless steel, magnesium-aluminum alloys, and high-temperature alloys, along with their anisotropy, are summarized and presented. The summary indicates that the factors leading to the anisotropy of the mechanical properties of metallic AM parts are either their unique microstructural features or manufacturing defects. This anisotropy can be improved by post-heat treatment. Finally, the most recent research on the subject of metal AM anisotropy is presented.

5.
R Soc Open Sci ; 11(7): 231697, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39076359

RESUMO

Single-cell technologies allow us to gain insights into cellular processes at unprecedented resolution. In stem cell and developmental biology snapshot data allow us to characterize how the transcriptional states of cells change between successive cell types. Here, we show how approximate Bayesian computation (ABC) can be employed to calibrate mathematical models against single-cell data. In our simulation study, we demonstrate the pivotal role of the adequate choice of distance measures appropriate for single-cell data. We show that for good distance measures, notably optimal transport with the Sinkhorn divergence, we can infer parameters for mathematical models from simulated single-cell data. We show that the ABC posteriors can be used (i) to characterize parameter sensitivity and identify dependencies between different parameters and (ii) to construct representations of the Waddington or epigenetic landscape, which forms a popular and interpretable representation of the developmental dynamics. In summary, these results pave the way for fitting mechanistic models of stem cell differentiation to single-cell data.

6.
CNS Neurosci Ther ; 30(7): e14874, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39056398

RESUMO

OBJECTIVE: This study explores the correlation between asymmetrical brain functional activity, gray matter asymmetry, and the severity of early-stage Parkinson's disease (PD). METHODS: Ninety-three early-stage PD patients (ePD, H-Y stages 1-2.5) were recruited, divided into 47 mild (ePD-mild, H-Y stages 1-1.5) and 46 moderate (ePD-moderate, H-Y stages 2-2.5) cases, alongside 43 matched healthy controls (HCs). The study employed the Hoehn and Yahr (H-Y) staging system for disease severity assessment and utilized voxel-mirrored homotopic connectivity (VMHC) for analyzing brain functional activity asymmetry. Asymmetry voxel-based morphometry analysis (VBM) was applied to evaluate gray matter asymmetry. RESULTS: The study found that, relative to HCs, both PD subgroups demonstrated reduced VMHC values in regions including the amygdala, putamen, inferior and middle temporal gyrus, and cerebellum Crus I. The ePD-moderate group also showed decreased VMHC in additional regions such as the postcentral gyrus, lingual gyrus, and superior frontal gyrus, with notably lower VMHC in the superior frontal gyrus compared to the ePD-mild group. A negative correlation was observed between the mean VMHC values in the superior frontal gyrus and H-Y stages, UPDRS, and UPDRS-III scores. No significant asymmetry in gray matter was detected. CONCLUSIONS: Asymmetrical brain functional activity is a significant characteristic of PD, which exacerbates as the disease severity increases, resembling the dissemination of Lewy bodies across the PD neurological framework. VMHC emerges as a potent tool for characterizing disease severity in early-stage PD.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Índice de Gravidade de Doença , Lateralidade Funcional/fisiologia
7.
Animals (Basel) ; 14(14)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39061511

RESUMO

Sonic hedgehog (Shh) is a component of the Hedgehog signaling pathway, playing an important role in regulating cell proliferation, differentiation, apoptosis, and the repair of damaged organisms. To further clarify the expression pattern of Shh gene in the secondary hair follicle growth cycle of cashmere goats and its mechanism of action on secondary hair follicle papilla cells, and improve cashmere quality, in this study, we took Inner Mongolia Albas white cashmere goats as the research objects and collected skin samples at different growth stages to obtain secondary hair follicles, detected Shh and its gene expression by RT-qPCR, Western blot, immunohistochemistry, and other techniques, while we also cultured DPCs in vitro. Shh gene overexpression and interference vectors were constructed, and the effects of Shh gene on the proliferation and apoptosis of DPCs were studied through cell transfection technology. The results showed that there are significant differences in Shh and its gene expression in the secondary hair follicle growth cycle skins of cashmere goats, with the highest expression level in anagen, followed by catagen, and the lowest expression level in telogen. Shh was mainly expressed in the inner root sheath, outer root sheath, and secondary hair follicle papilla. After the overexpression of Shh gene, the proliferation and vitality of the hair papilla cells were enhanced compared to the interference group. After Shh gene interference, the apoptosis rate of the cells increased, indicating that Shh gene can regulate downstream Ptch, Smo, and Gli2 gene expression to promote the proliferation of DPCs, and thus form its expression pattern in the secondary hair follicle growth cycle of cashmere goats.

8.
Adv Sci (Weinh) ; : e2404213, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38981036

RESUMO

Recently emerging lithium ternary chlorides have attracted increasing attention for solid-state electrolytes (SSEs) due to their favorable combination between ionic conductivity and electrochemical stability. However, a noticeable discrepancy in Li-ion conductivity persists between chloride SSEs and organic liquid electrolytes, underscoring the need for designing novel chloride SSEs with enhanced Li-ion conductivity. Herein, an intriguing trigonal structure (i.e., Li3SmCl6 with space group P3112) is identified using the global structure searching method in conjunction with first-principles calculations, and its potential for SSEs is systematically evaluated. Importantly, the structure of Li3SmCl6 exhibits a high ionic conductivity of 15.46 mS cm-1 at room temperature due to the 3D lithium percolation framework distinct from previous proposals, associated with the unique in-plane cation ordering and stacking sequences. Furthermore, it is unveiled that Li3SmCl6 possesses a wide electrochemical window of 0.73-4.30 V vs Li+/Li and excellent chemical interface stability with high-voltage cathodes. Several other Li3MCl6 (M = Er, and In) materials with isomorphic structures to Li3SmCl6 are also found to be potential chloride SSEs, suggesting the broader applicability of this structure. This work reveals a new class of ternary chloride SSEs and sheds light on strategy for structure searching in the design of high-performance SSEs.

9.
Int J Biol Macromol ; 277(Pt 1): 134196, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39069053

RESUMO

Lipases are increasingly attracting attention in green and sustainable biodiesel production. Currently, the research emphasis lies in immobilizing unstable lipase onto carriers to enhance its performance. Polyacrylonitrile fiber (PANF) is considered to be a promising material for lipase immobilization due to its excellent properties. In this study, functional carriers with regulated surface hydrophobicity were obtained by loading functional groups on PANF via reversible addition-fragmentation chain transfer (RAFT) polymerized modification, and Candida rugosa lipase (CRL) was covalently immobilized on the carrier with glutaraldehyde as a linker. By employing this optimized biocatalyst PANF@BMA&2VImBr-NH2-CRL in the transesterification process, the yield of biodiesel derived from soybean oil reached an impressive 92.7 %. The outstanding performance can be attributed to the activation of lipase interface induced by hydrophobic microenvironment derived from alkyl ester on the carrier skeleton. Moreover, the stability and storage performance of immobilized lipase were significantly improved. The immobilized lipase exhibited facile recovery and maintained a consistent biodiesel yield of 80.9 % even after undergoing 5 cycles of reuse, thereby highlighting its potential for sustainable production. To sum up, our research demonstrates that the designed and prepared process of PANF-supported lipase offers a promising approach for enzyme immobilization, thereby presenting extensive potential applications in the field of biotechnology.


Assuntos
Resinas Acrílicas , Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Lipase/química , Lipase/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Resinas Acrílicas/química , Biocatálise , Polimerização , Esterificação , Biocombustíveis , Saccharomycetales/enzimologia , Estabilidade Enzimática
10.
ChemSusChem ; : e202400738, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837662

RESUMO

Modifying the interface between the lithium metal anode (LMA) and the electrolyte is crucial for achieving high-performance lithium metal batteries (LMBs). Recent research indicates that altering Li-metal interfaces with polymer coatings is an effective approach to extend LMBs' cycling lifespan. However, the physical properties of these polymer-Li interfaces have not yet been fully investigated. Therefore, the structural stability, electronic conductivity, and ionic conductivity of polymer-Li interfaces were examined based on first-principles calculations in this study. Several representative polymer compounds utilized in LMBs were assessed, including polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), and polyethylene oxide (PEO). Our research revealed that lithium fluoride is formed upon fluoropolymer degradation, explaining previously observed experimental results. Polymers containing nitrile groups exhibit strong adhesion to lithium metal, facilitating the formation of the stable interface layer. Regarding electronic conductivity, the fluoropolymers preserve a good insulating property, which diminished marginally in the presence of lithium, but that of PAN and PEO significantly reduces. Additionally, lithium diffusion on PTFE and PEO demonstrates low diffusion barriers and high coefficients, enabling easy transportation. Overall, our investigation reveals that the interfaces formed between various polymers and LMA have distinct characteristics, providing new fundamental insights for designing composites with tailored interface properties.

11.
ACS Nano ; 18(27): 17950-17957, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38916519

RESUMO

The pursuit of high energy density in lithium batteries has driven the development of efficient electrodes with low levels of inactive components. Herein, a facile approach involving the use of π-π stacked nigrosine@carbon nanotube nanocomposites as an all-in-one additive for a LiFePO4 cathode has been developed. This design significantly reduces the proportion of inactive substances within the cathode, resulting in a battery that exhibits a high specific capacity of 143 mAh g-1 at a 1 C rate and shows commendable cyclic performance. Furthermore, the elimination of rigid current collectors endows the electrode with flexibility, offering avenues for future wearable energy storage devices.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38829385

RESUMO

Garlic exhibits hypolipidemic, hypoglycemic, and cardiovascular benefits. The inconsistent results of garlic preparations on adipogenesis have caused more confusion in the public and academia. The compounds responsible for the anti-adipogenesis effect of garlic remain unknown. The present study aimed to verify the real anti-adipogenesis and anti-obesity component in garlic and explored its possible effects in metabolic syndrome. We verified the real anti-adipogenesis and anti-obesity components of garlic in 3T3-L1 preadipocytes and a 10-week-high fat diet (HFD)-induced obese mice. In vitro, two water-soluble and four typical lipid-soluble compounds of garlic were tested for their anti-adipogenesis. Then, the water-soluble compound, alliin, and two processing methods produced garlic oils, were evaluated in vivo study. Mice received oral administration of alliin (25 mg/kg) and garlic oils (15 mg/kg) daily for 8 weeks. Serum lipids, parameters of obesity, and indicators involved in regulating glycolipid metabolism were examined. Our findings confirmed that both water-soluble and lipid-soluble organosulfur compounds of garlic contributed to garlic's anti-adipogenesis effect, in which water-soluble sulfides, especially alliin, exhibited greater potency. Alliin possessed potent effects of anti-obesity and improvement in glucose and lipid metabolism in HFD-induced obese mice. Alliin mediated these effects partly attributed to its modulation of enzymatic activities within glycolipid metabolism and activating PPARγ signaling pathway. In contrast to odorous lipid-soluble sulfides, alliin is odorless, stable, and safe, and is an ideal nutraceutical or even medicinal candidates for the treatment of metabolic diseases. Alliin could be used to standardize the quality of garlic products.

14.
Int J Biol Macromol ; 271(Pt 2): 132716, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38815941

RESUMO

Nanoparticle-containing sizing agents are essential for the overall performance of high-quality carbon fiber (CF) composites. However, the uneven dispersion of nanoparticles often leads to agglomeration on the surface of CF after sizing, consequently diminishing the material properties. In this study, the properties of cellulose nanofibers (CNFs) that can respond to magnetic and electric fields were utilized to achieve three-dimensional to one-dimensional orientations in CFs containing sizing agents. Cobalt ferrite (CoFe2O4) was utilized to enhance the response of CNFs to a magnetic field, and subsequently, it was combined with an electric field to attain a higher degree of orientation. The occurrence of nanoparticle agglomeration is diminished on CF surface, while establishing a structured network. The flexural strength and thermal conductivity of CF composites treated with CoFe2O4 self-assembled CNF sizing agent exhibit an increase of 54.23 % and 57.5 %, respectively, compared to those of desized CF composites, when subjected to magnetic and electric fields. Consequently, the approach can depolymerize the nano-fillers within the sizing agent and orient it into the carbon fiber under the influence of magnetic and electric fields, effectively improving the mechanical properties and thermal conductivity of the composite material.


Assuntos
Fibra de Carbono , Celulose , Campos Magnéticos , Nanofibras , Nanofibras/química , Celulose/química , Fibra de Carbono/química , Compostos Férricos/química , Cobalto/química , Eletricidade , Condutividade Térmica , Nanocompostos/química
15.
Am J Chin Med ; 52(4): 1155-1172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38790087

RESUMO

Colorectal cancer is the third leading cause of cancer-related death worldwide. Hence, there is a need to identify new therapeutic agents to improve the current repertoire of therapeutic drugs. Wogonin, a flavonoid from the herbal medicine Scutellaria baicalensis, has unique antitumor activity. Our study aimed to further explore the inhibitory effects of wogonin on colorectal cancer and its specific mechanism. The results showed that wogonin significantly inhibited the proliferation of colorectal cancer cells as well as their ability to invade and metastasize. We detected phosphorylation of tumor-associated signaling pathways using a phosphorylated protein microarray and found that wogonin intervention significantly inhibited the phosphorylation level of the AKT protein in colorectal cancer cells. Through in vitro and in vivo experiments, it was confirmed that wogonin exerted its antitumor effects against colorectal cancer by inhibiting phosphorylation in the AKT pathway. Our discovery of wogonin as an inhibitor of AKT phosphorylation provides new opportunities for the pharmacological treatment of colorectal cancer.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Flavanonas , Proteínas Proto-Oncogênicas c-akt , Scutellaria baicalensis , Transdução de Sinais , Flavanonas/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosforilação/efeitos dos fármacos , Humanos , Proliferação de Células/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Scutellaria baicalensis/química , Animais , Antineoplásicos Fitogênicos/farmacologia , Fitoterapia
16.
J Ethnobiol Ethnomed ; 20(1): 52, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755671

RESUMO

BACKGROUND: The Baiku Yao, primarily residing in Guangxi and Guizhou provinces of China, is a distinctive branch of the Yao ethnic group, known for their profound cultural preservation and unique ethnobotanical knowledge. This study investigates the Baiku Yao community's utilization of traditional food plants, focusing on the relationship between their dietary practices and the local biodiversity within their mountainous living environment. It aims to illuminate the cultural significance and survival strategies embedded in their ethnobotanical knowledge, highlighting the potential for sustainable living and biodiversity conservation. METHODS: Through ethnobotanical surveys, key informant interviews, and quantitative analysis techniques such as the cultural food significance index (CFSI) and relative frequency of citations (RFC), this research systematically documents the diversity and cultural importance of edible plants in the Baiku Yao community. The study assesses how these plants contribute to the community's diet, traditional medicine, and overall cultural practices. RESULTS: A total of 195 traditional edible plants were documented, belonging to 142 genera and 68 families, with a significant concentration in certain families such as Asteraceae, Rosaceae, and Fabaceae. The Baiku Yao diet prominently features herbaceous plants, with wild (103 species) and cultivated (89 species) varieties as diverse food sources. They utilize various plant parts, particularly fruits and leaves, for multiple purposes, including nutrition, medicine, and fodder. Their processing techniques, from raw to fermented, showcase a rich culinary tradition and emphasize a holistic use of plants for enhancing diet and health in a concise overview. The RFC and CFSI analyses reveal a deep cultural reliance on a variety of plant species, with a notable emphasis on vegetables, fruits, spices, and medicinal herbs. Specific plants like Zingiber officinale, Zea mays, and Oryza sativa were highlighted for their high cultural significance. The study also uncovers the multifunctional use of these plants, not only as food but also for medicinal purposes, fodder, and other cultural applications, reflecting the Baiku Yao's profound ecological wisdom and their harmonious coexistence with nature. CONCLUSION: The findings emphasize the rich ethnobotanical knowledge possessed by the Baiku Yao, underscoring the importance of documenting, safeguarding, and transmitting this invaluable traditional knowledge. This study contributes to a deeper understanding of cultural heritage and biodiversity conservation, advocating for concerted efforts to protect such traditional practices against the threats of modernization and cultural erosion.


Assuntos
Conservação dos Recursos Naturais , Etnobotânica , Plantas Comestíveis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biodiversidade , China , Dieta , Etnicidade , Conhecimento , Plantas Comestíveis/classificação , Plantas Medicinais , Adulto Jovem , Adulto , Idoso , Idoso de 80 Anos ou mais
17.
Adv Mater ; 36(28): e2400639, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38664988

RESUMO

Lithium-sulfur (Li-S) batteries, operated through the interconversion between sulfur and solid-state lithium sulfide, are regarded as next-generation energy storage systems. However, the sluggish kinetics of lithium sulfide deposition/dissolution, caused by its insoluble and insulated nature, hampers the practical use of Li-S batteries. Herein, leaf-like carbon scaffold (LCS) with the modification of Mo2C clusters (Mo2C@LCS) is reported as host material of sulfur powder. During cycles, the dissociative Mo ions at the Mo2C@LCS/electrolyte interface are detected to exhibit competitive binding energy with Li ions for lithium sulfide anions, which disrupts the deposition behavior of crystalline lithium sulfide and trends a shift in the configuration of lithium sulfide toward an amorphous structure. Combining the related electrochemical study and first-principle calculation, it is revealed that the formation of amorphous lithium sulfides shows significantly improved kinetics for lithium sulfide deposition and decomposition. As a result, the obtained Mo2C@LCS/S cathode shows an ultralow capacity decay rate of 0.015% per cycle at a high mass loading of 9.5 mg cm-2 after 700 cycles. More strikingly, an ultrahigh sulfur loading of 61.2 mg cm-2 can also be achieved. This work defines an efficacious strategy to advance the commercialization of Mo2C@LCS host for Li-S batteries.

18.
J Stroke Cerebrovasc Dis ; 33(7): 107736, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38679216

RESUMO

BACKGROUND: Ischemic stroke remains the predominant contributor to mortality and disability globally. Microglia undergo rapid activation and initiate inflammatory cascade reactions by phenotypic polarization, participating in the regulation of inflammatory injury and tissue repair post-ischemic stroke. Regulating microglia-mediated neuroinflammation is a promising therapeutic strategy for ischemic stroke. Previously, we designed and synthesized a novel p55PIK inhibitor, TAT-N15 polypeptide, which presents inhibitive activity on NF-κB signaling-mediated inflammation in acute conjunctivitis and allergic rhinitis. The present study aimed to explore the therapeutic effect and mechanism of TAT-N15 on ischemia stroke. METHODS: The mouse model of transient cerebral ischemia was made using the intraluminal filament method. After being treated with daily intraperitoneal injections of TAT-N15 (10 mg/kg) for 7 d, the neurological outcomes and the cerebral infarction volume were evaluated. Histopathology of the ischemia cerebral hemisphere was observed by H&E and Nissl staining. Neuronal survival, astrogliosis, and co-labeling of CD86/Iba1 and CD206/Iba1 were detected by immunofluorescence. The cell apoptosis was estimated by TUNEL staining. The expression levels of apoptosis-associated proteins, proinflammatory cytokines, protein markers of M1 and M2 microglia, and the phosphorylation of NF-κB and STAT3 proteins in the ischemic penumbra were detected by Western blot. RESULTS: TAT-N15 treatment significantly decreased the infarct volume and alleviated neurological functional impairment, neuronal injury, and neuron apoptosis. Meanwhile, TAT-N15 treatment restrained the activation of microglia and astrocytes as well as the protein expression of proinflammatory cytokine in ischemic penumbra. Additionally, the administration of TAT-N15 treatment resulted in a significant reduction in the density of M1 phenotype microglia while concurrently increasing the density of M2 phenotype microglia within the ischemic penumbra. Finally, mechanical analysis unveiled that TAT-N15 exerted a substantial inhibitory effect on the protein expression of phosphorylated STAT3 and NF-κB. CONCLUSION: TAT-N15 may inhibit neuroinflammation via regulating microglia activation and polarization through the STAT3/NF-κB pathway, which exhibits the neuroprotection effect in ischemic stroke.


Assuntos
Anti-Inflamatórios , Apoptose , Modelos Animais de Doenças , Mediadores da Inflamação , Camundongos Endogâmicos C57BL , Microglia , NF-kappa B , Doenças Neuroinflamatórias , Fármacos Neuroprotetores , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Fármacos Neuroprotetores/farmacologia , Masculino , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/metabolismo , Ataque Isquêmico Transitório/patologia , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-38606549

RESUMO

PtRu alloys have been recognized as the state-of-the-art catalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). However, their applications in DMFCs are still less efficient in terms of both catalytic activity and durability. Rare earth (RE) metals have been recognized as attractive elements to tune the catalytic activity, while it is still a world-class challenge to synthesize well-dispersed Pt-RE alloys. Herein, we developed a novel hydrogen-assisted magnesiothermic reduction strategy to prepare a highly dispersed carbon-supported lutetium-doped PtRu catalyst with ultrafine nanoclusters and atomically dispersed Ru sites. The PtRuLu catalyst shows an outstanding high electrochemical surface area (ECSA) of 239.0 m2 gPt-1 and delivers an optimized MOR mass activity and specific activity of 632.5 mA mgPt-1 and 26 A cmPt-2 at 0.4 V vs saturated calomel electrode (SCE), which are 3.6 and 3.5 times of commercial PtRu-JM and an order higher than PtLu, respectively. These novel catalysts have been demonstrated in a high-temperature direct methanol fuel cell running in a temperature range of 180-240 °C, achieving a maximum power density of 314.3 mW cm-2. The AC-STEM imaging, in situ ATR-IR spectroscopy, and DFT calculations disclose that the high performance is resulted from the highly dispersed PtRuLu nanoclusters and the synergistic effect of the atomically dispersed Ru sites with PtRuLu nanoclusters, which significantly reduces the CO* intermediates coverage due to the promoted water activation to form the OH* to facilitate the CO* removal.

20.
World J Clin Cases ; 12(8): 1448-1453, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38576799

RESUMO

BACKGROUND: Clear cell sarcoma (CCS) is a rare soft-tissue sarcoma. The most common metastatic sites for CCS are the lungs, bones and brain. CCS is highly invasive and mainly metastasizes to the lung, followed by the bone and brain; however, pancreatic metastasis is relatively rare. CASE SUMMARY: We report on a rare case of CCS with pancreatic metastasis in a 47-year-old man. The patient had a relevant medical history 3 years ago, with abdominal pain as the main clinical manifestation. No abnormalities were observed on physical examination and the tumor was found on abdominal computed tomography. Based on the medical history and postoperative pathology, the patient was diagnosed with CCS with pancreatic metastasis. The patient was successfully treated with surgical interventions, including distal pancreatectomy and splenectomy. CONCLUSION: This report summarizes the available treatment modalities for CCS and the importance of regular postoperative follow-up for patients with CCS.

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