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1.
ACS Appl Mater Interfaces ; 16(12): 14902-14911, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38484086

RESUMO

Li-rich Mn-based layered oxides (LMLOs) are expected to be the most promising high-capacity cathodes for the next generation of lithium-ion batteries (LIBs). However, the poor cycling stability and kinetics performance of polycrystalline LMLOs restrict their practical applications due to the anisotropic lattice stress and crack propagation during cycling. Herein, B-doped micron-sized single-crystal Co-free LMLOs were obtained by molten-salt (LiNO3 and H3BO3)-assisted sintering. The results reveal that the low-melting-point molten salt can serve as liquid-phase media to improve the efficiency of atomic mass transfer and crystal nucleation and growth. The modified single-crystal LMLO cathodes can resist the accumulation of anisotropic stress and strain during the cycling and reduce interface side reactions, thus achieving excellent high-voltage stability and kinetics performance. The reversible specific capacity of the single crystals is 210.8 mAh g-1 at 1C with a voltage decay rate of 1.95 mV/cycle and up to 161.1 mAh g-1 at 10C with a capacity retention of 81.06% after 200 cycles.

2.
Dis Markers ; 2024: 9936295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38549717

RESUMO

Objective: Osteoarthritis (OA) is a commonly known prevalent joint disease, with limited therapeutic methods. This study aimed to investigate the expression of plasma microRNA-320c (miR-320c) in patients with knee OA and to explore the clinical value and potential mechanism of miR-320c in knee OA. Methods: Forty knee OA patients and 20 healthy controls were enrolled. The levels of plasma miR-320c and plasma inflammatory cytokines were measured by real-time PCR or ELISA. Correlations of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and cytokine levels with the miR-320c expression level were evaluated by Pearson correlation analysis. Then, a receiver operating characteristic (ROC) curve was drawn to analyse the diagnostic value of miR-320c in OA. Finally, the interaction of miR-320c and cAMP responsive element binding protein 5 (CREB5) was determined using a luciferase reporter assay, and the effect of CREB5 on the cAMP pathway was assessed. Results: The expression level of plasma miR-320c was significantly higher in OA patients than in healthy controls (p < 0.05). The increased plasma miR-320c level was positively correlated with the WOMAC score (r = 0.796, p < 0.001) and the plasma interleukin (IL)-1ß (r = 0.814, p < 0.001) and IL-6 (r = 0.695, p < 0.001) levels in patients with OA. ROC curve analysis demonstrated the relatively high diagnostic accuracy of plasma miR-320c for OA. Furthermore, the luciferase reporter assay results showed that miR-320c regulates CREB5 expression by binding to the CREB5 3'-untranslated region. Moreover, suppression of CREB5 significantly reduced the expression levels of c-fos and c-jun. Conclusion: Our results indicate that plasma miR-320c may serve as a potential novel predictor of the severity of knee OA and that miR-320c may play an important role in the pathogenesis of OA through inhibiting the cAMP pathway by targeting CREB5.


Assuntos
MicroRNAs , Osteoartrite do Joelho , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/metabolismo , Condrócitos/metabolismo , Biomarcadores/metabolismo , Luciferases/metabolismo , Interleucina-1beta/metabolismo , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/metabolismo
3.
Int J Cancer ; 154(11): 1877-1889, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429857

RESUMO

In recent years, breast cancer (BC) has surpassed lung cancer as the most common malignant tumor worldwide and remains the leading cause of cancer death in women. The etiology of BC usually involves dysregulation of epigenetic mechanisms and aberrant expression of certain non-coding RNAs (ncRNAs). N6-methyladenosine (m6A), the most prevalent RNA modification in eukaryotes, widely exists in ncRNAs to affect its biosynthesis and function, and is an important regulator of tumor-related signaling pathways. Interestingly, ncRNAs can also regulate or target m6A modification, playing a key role in cancer progression. However, the m6A-ncRNAs regulatory network in BC has not been fully elucidated, especially the regulation of m6A modification by ncRNAs. Therefore, in this review, we comprehensively summarize the interaction mechanisms and biological significance of m6A modifications and ncRNAs in BC. Meanwhile, we also focused on the clinical application value of m6A modification in BC diagnosis and prognosis, intending to explore new biomarkers and potential therapeutic targets.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Feminino , Humanos , Neoplasias da Mama/genética , Adenosina/genética , Epigênese Genética , RNA não Traduzido/genética
4.
Sci Total Environ ; 923: 171331, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38428609

RESUMO

Staphylococcus aureus is one of the most frequently detected foodborne pathogens in cold chain foods. Worryingly, small colony variants (SCVs) can survive in cold environments for a long time and can revert to rapidly growing cells in suitable environments, causing serious food safety issues. This study investigated the underlying mechanism of SCV formation at low temperature (4 °C) via comparative genomics. Multilocus sequence typing (MLST) of 105 strains of S. aureus was divided into 9 sequence types. The ST352 strains exhibited the greatest tolerance to low temperature, with a mean reduction in survival rate of 10.34 % (p < 0.05). Comparative genomics revealed a total of 1941 core genes in the three S. aureus strains, and BB-1 had 468 specific genes, which were enriched mainly in translation, DNA recombination, DNA repair, metabolic pathways, two-component systems, and quorum sensing. Molecular docking analysis revealed that the binding of the RsbW protein to the SigB protein of BB-1 decreased due to base mutations in rsbW, while the binding to the RsbV protein was enhanced. In addition, the results of real-time quantitative PCR showed that the RsbV-RsbW/SigB system of BB-1 may play a role in the low-temperature survival of S. aureus and the formation of SCVs. These results suggest that genes specific to BB-1 may contribute to the mechanism of adaptation to low temperature and the formation of SCVs. This study helps elucidate the causes of SCV formation by S. aureus at low temperature at the molecular level and provides a basis for exploring the safety control of cold chain food environments.


Assuntos
Proteínas de Bactérias , Staphylococcus aureus , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Tipagem de Sequências Multilocus , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Simulação de Acoplamento Molecular , Temperatura , Genômica , Antibacterianos/metabolismo
5.
Sci Total Environ ; 922: 171234, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428612

RESUMO

As a ubiquitous pollutant in the environment, hexafluoropropylene oxide trimer acid (HFPO-TA) has been proven to have strong hepatotoxicity. However, the underlying mechanism is still unclear. Consequently, in vivo and in vitro models of HFPO-TA exposure were established to investigate the detrimental effects of HFPO-TA on the liver. In vivo, we discovered that HFPO-TA enhanced endoplasmic reticulum (ER)-mitochondrial association, caused mitochondrial oxidative damage, activated ER stress, and induced apoptosis in mouse livers. In vitro experiments confirmed that IP3R overexpression on ER structure increased mitochondrial calcium levels, which led to mitochondrial damage and mitochondria-dependent apoptosis in HepG2 cells exposed to HFPO-TA. Subsequently, damaged mitochondria released a large amount of mitochondrial ROS, which activated ER stress and ER stress-dependent apoptosis. In conclusion, this study demonstrates that HFPO-TA can induce apoptosis by regulating the crosstalk between ER and mitochondria, ultimately leading to liver damage. These findings reveal the significant hepatotoxicity of HFPO-TA and its potential mechanisms.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Fluorocarbonos , Mitocôndrias , Propionatos , Animais , Camundongos , Apoptose , Retículo Endoplasmático/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo
7.
J Agric Food Chem ; 72(11): 5955-5965, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38451160

RESUMO

The worldwide prevalence of Aflatoxin B1 (AFB1), which contaminates feedstock and food, is on the rise. AFB1 inhibits testosterone (T) biosynthesis, but the mechanism is not yet clear. By establishing in vivo and in vitro models, this study found the number of Leydig cells (LCs), T content, and the expression of T biosynthesis key enzymes were suppressed after AFB1 treatment. AFB1 exposure also increased reactive oxygen species (ROS) and promoted mitochondrial injury and mitochondrial pathway apoptosis. Moreover, the AMPK signaling pathway was activated, and using an AMPK inhibitor relieved apoptosis and the suppressed T biosynthesis key enzymes of LCs caused by AFB1 through regulating downstream p53 and Nur77. Additionally, adding ROS intervention could inhibit AMPK activation and alleviate the decreased T content caused by AFB1. In summary, AFB1 promotes the apoptosis of LCs and inhibits T biosynthesis key enzyme expression via activating the ROS/AMPK signaling pathway, which eventually leads to T synthesis disorder.


Assuntos
Proteínas Quinases Ativadas por AMP , Aflatoxina B1 , Camundongos , Masculino , Animais , Espécies Reativas de Oxigênio/metabolismo , Aflatoxina B1/toxicidade , Aflatoxina B1/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Transdução de Sinais , Testosterona , Apoptose , Estresse Oxidativo
8.
mBio ; 15(2): e0201523, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38197633

RESUMO

SCS7 is a fatty acid 2-hydroxylase required for the synthesis of inositol phosphorylceramide but is not essential for normal growth in Saccharomyces cerevisiae. Here, we demonstrate that the Colletotrichum siamense SCS7 homolog CsSCS7 plays a key role in hyphal growth. The CsSCS7 deletion mutant showed strong hyphal growth inhibition, small conidia, and marginally reduced sporulation and also resulted in a sharp reduction in the full virulence and increasing the fungicide sensitivity. The three protein domains (a cytochrome b5 domain, a transmembrane domain, and a hydroxylase domain) are important to CsSCS7 protein function in hyphal growth. The fatty acid assay results revealed that the CsSCS7 gene is important for balancing the contents of multiple mid-long- and short-chain fatty acids. Additionally, the retarded growth and virulence of C. siamense ΔCsSCS7 can be recovered partly by the reintroduction of homologous sequences from Magnaporthe oryzae and Fusarium graminearum but not SCS7 of S. cerevisiae. In addition, the spraying of C. siamense with naked CsSCS7-double-stranded RNA (dsRNAs), which leads to RNAi, increases the inhibition of hyphal growth and slightly decreases disease lesions. Then, we used nano material Mg-Al-layered double hydroxide as carriers to deliver dsRNA, which significantly enhanced the control effect of dsRNA, and the lesion area was obviously reduced. These data indicated that CsSCS7 is an important factor for hyphal growth and affects virulence and may be a potential control target in C. siamense and even in filamentous plant pathogenic fungi.IMPORTANCECsSCS7, which is homologous to yeast fatty acid 2-hydroxylase SCS7, was confirmed to play a key role in the hyphal growth of Colletotrichum siamense and affect its virulence. The CsSCS7 gene is involved in the synthesis and metabolism of fatty acids. Homologs from the filamentous fungi Magnaporthe oryzae and Fusarium graminearum can recover the retarded growth and virulence of C. siamense ΔCsSCS7. The spraying of double-stranded RNAs targeting CsSCS7 can inhibit hyphal growth and reduce the disease lesion area to some extent. After using nano material Mg-Al layered double hydroxide as carrier, the inhibition rates were significantly increased. We demonstrated that CsSCS7 is an important factor for hyphal growth and affects virulence and may be a potential control target in C. siamense and even in filamentous plant pathogenic fungi.


Assuntos
Ascomicetos , Colletotrichum , Proteínas Fúngicas , Fusarium , Proteínas Fúngicas/genética , Saccharomyces cerevisiae/metabolismo , Colletotrichum/genética , Oxigenases de Função Mista/genética , Ácidos Graxos , Hidróxidos , Peptídeos e Proteínas de Sinalização Intercelular
9.
Nano Lett ; 24(4): 1153-1159, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232325

RESUMO

Twin structures possess distinct physical and chemical properties by virtue of their specific twin configuration. However, twinning and detwinning processes are not fully understood on the atomic scale. Integrating in situ high resolution transmission electron microscopy and molecular dynamic simulations, we find tensile strain in the asymmetrical 5-fold twins of Au nanoparticles leads to twin boundary migration through dislocation sliding (slipping of an atomic layer) along twin boundaries and dislocation reactions at the 5-fold axis under an electron beam. Migration of one or two layers of twin planes is governed by energy barriers, but overall, the total energy, including surface, lattice strain, and twin boundary energy, is relaxed after consecutive twin boundary migration, leading to a detwinning process. In addition, surface rearrangement of 5-fold twinned nanoparticles can aid in the detwinning process.

10.
Small ; : e2310423, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263809

RESUMO

Infrared nonlinear optical (IR NLO) materials play significant roles in laser technology. The novel functional building units (FBUs) are of great importance in constructing NLO materials with strong second harmonic generation (SHG). Herein, polysulfide anion [Sx ]2- (x = 2, 3, 4, 5) units are investigated on NLO-related properties and structure-performance relationships. Theoretical calculations uncover that the [Sx ]2- (x = 2, 3, 4, 5) units are potential IR NLO FBUs with large polarizability anisotropy (δ), hyperpolarizability (ß) and wide HOMO-LUMO gap. Fourteen crystals including [Sx ]2- (x = 2, 3, 4, 5) units are calculated and analyzed. The results show that these units can result in a wide IR transmittance range, significant SHG effects, wide band gap Eg (Na2 S4 : Eg  = 3.09 eV), and large birefringence Δn [BaS3 (P21 21 2): Δn = 0.70]. More importantly, it is highlighted that the crystal materials including with [Sx ]2- (x = 2, 3, 4, 5) groups are good candidates for the exploration of the outstanding IR NLO materials.

13.
Adv Mater ; 36(13): e2308380, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38134206

RESUMO

Protonation of oxide cathodes triggers surface transition metal dissolution and accelerates the performance degradation of Li-ion batteries. While strategies are developed to improve cathode material surface stability, little is known about the effects of protonation on bulk phase transitions in these cathode materials or their sodium-ion battery counterparts. Here, using NaNiO2 in electrolytes with different proton-generating levels as model systems, a holistic picture of the effect of incorporated protons is presented. Protonation of lattice oxygens stimulate transition metal migration to the alkaline layer and accelerates layered-rock-salt phase transition, which leads to bulk structure disintegration and anisotropic surface reconstruction layers formation. A cathode that undergoes severe protonation reactions attains a porous architecture corresponding to its multifold performance fade. This work reveals that interactions between electrolyte and cathode that result in protonation can dominate the structural reversibility/stability of bulk cathodes, and the insight sheds light for the development of future batteries.

14.
Innovation (Camb) ; 5(1): 100540, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38144039

RESUMO

MXenes have aroused intensive enthusiasm because of their exotic properties and promising applications. However, to date, they are usually synthesized by etching technologies. Developing synthetic technologies provides more opportunities for innovation and may extend unexplored applications. Here, we report a bottom-up gas-phase synthesis of Cl-terminated MXene (Ti2CCl2). The gas-phase synthesis endows Ti2CCl2 with unique surface chemistry, high phase purity, and excellent metallic conductivity, which can be used to accelerate polysulfide conversion kinetics and dramatically prolong the cyclability of Li-S batteries. In-depth mechanistic analysis deciphers the origin of the formation of Ti2CCl2 and offers a paradigm for tuning MXene chemical vapor deposition. In brief, the gas-phase synthesis transforms the synthesis of MXenes and unlocks the hardly achieved potentials of MXenes.

16.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139168

RESUMO

Plasma membrane H+-ATPases (PMAs) play an important role in the pathogenicity of pathogenic fungi. Lipid droplets are important storage sites for neutral lipids in fungal conidia and hyphae and can be used by plant pathogenic fungi for infection. However, the relationship between plasma membrane H+-ATPase, lipid droplets and virulence remains unclear. Here, we characterized a plasma membrane H+-ATPase, CsPMA2, that plays a key role in lipid droplet formation, appresorial development and virulence in C. siamense. Deletion of CsPMA2 impaired C. siamense conidial size, conidial germination, appressorial development and virulence but did not affect hyphal growth. ΔCsPMA2 increased the sensitivity of C. siamense to phytic acid and oxalic acid. CsPMA2 was localized to lipids on the plasma membrane and intracellular membrane. Deletion of CsPMA2 significantly inhibited the accumulation of lipid droplets and significantly affected the contents of some species of lipids, including 12 species with decreased lipid contents and 3 species with increased lipid contents. Furthermore, low pH can inhibit CsPMA2 expression and lipid droplet accumulation. Overall, our data revealed that the plasma membrane H+-ATPase CsPMA2 is involved in the regulation of lipid droplet formation and affects appressorial development and virulence in C. siamense.


Assuntos
Colletotrichum , Gotículas Lipídicas , Virulência , Gotículas Lipídicas/metabolismo , Proteínas Fúngicas/metabolismo , Lipídeos , Membrana Celular/metabolismo , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo
17.
J Am Chem Soc ; 145(48): 26016-26027, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37976467

RESUMO

Proton transfer is critically important to many electrocatalytic reactions, and directed proton delivery could open new avenues for the design of electrocatalysts. However, although this approach has been successful in molecular electrocatalysis, proton transfer has not received the same attention in heterogeneous electrocatalyst design. Here, we report that a metal oxide proton relay can be built within heterogeneous electrocatalyst architectures and improves the kinetics of electrochemical hydrogen evolution and oxidation reactions. The volcano-type relationship between activity enhancement and pKa of amine additives confirms this improvement; we observe maximum rate enhancement when the pKa of a proton relay matches the pH of the electrolyte solution. Density-functional-theory-based reactivity studies reveal a decreased proton transfer energy barrier with a metal oxide proton relay. These findings demonstrate the possibility of controlling the proton delivery and enhancing the reaction kinetics by tuning the chemical properties and structures at heterogeneous interfaces.

19.
Antioxidants (Basel) ; 12(10)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37891963

RESUMO

Drought poses a significant challenge to global wheat production, and the application of exogenous phytohormones offers a convenient approach to enhancing drought tolerance of wheat. However, little is known about the molecular mechanism by which strigolactones (SLs), newly discovered phytohormones, alleviate drought stress in wheat. Therefore, this study is aimed at elucidating the physiological and molecular mechanisms operating in wheat and gaining insights into the specific role of SLs in ameliorating responses to the stress. The results showed that SLs application upregulated the expression of genes associated with the antioxidant defense system (Fe/Mn-SOD, PER1, PER22, SPC4, CAT2, APX1, APX7, GSTU6, GST4, GOR, GRXC1, and GRXC15), chlorophyll biogenesis (CHLH, and CPX), light-harvesting chlorophyll A-B binding proteins (WHAB1.6, and LHC Ib-21), electron transfer (PNSL2), E3 ubiquitin-protein ligase (BB, CHIP, and RHY1A), heat stress transcription factor (HSFA1, HSFA4D, and HSFC2B), heat shock proteins (HSP23.2, HSP16.9A, HSP17.9A, HSP21, HSP70, HSP70-16, HSP70-17, HSP70-8, HSP90-5, and HSP90-6), DnaJ family members (ATJ1, ATJ3, and DJA6), as well as other chaperones (BAG1, CIP73, CIPB1, and CPN60I). but the expression level of genes involved in chlorophyll degradation (SGR, NOL, PPH, PAO, TIC55, and PTC52) as well as photorespiration (AGT2) was found to be downregulated by SLs priming. As a result, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were enhanced, and chlorophyll content and photosynthetic rate were increased, which indicated the alleviation of drought stress in wheat. These findings demonstrated that SLs alleviate drought stress by promoting photosynthesis through enhancing chlorophyll levels, and by facilitating ROS scavenging through modulation of the antioxidant system. The study advances understandings of the molecular mechanism underlying SLs-mediated drought alleviation and provides valuable insights for implementing sustainable farming practice under water restriction.

20.
Breast Cancer Res ; 25(1): 126, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858183

RESUMO

Breast cancer metastasis is a complex, multi-step process, with high cellular heterogeneity between primary and metastatic breast cancer, and more complex interactions between metastatic cancer cells and other cells in the tumor microenvironment. High-resolution single-cell transcriptome sequencing technology can visualize the heterogeneity of malignant and non-malignant cells in the tumor microenvironment in real time, especially combined with spatial transcriptome analysis, which can directly compare changes between different stages of metastatic samples. Therefore, this study takes single-cell analysis as the first perspective to deeply explore special or rare cell subpopulations related to breast cancer metastasis, systematically summarizes their functions, molecular features, and corresponding treatment strategies, which will contribute to accurately identify, understand, and target tumor metastasis-related driving events, provide a research basis for the mechanistic study of breast cancer metastasis, and provide new clues for its personalized precision treatment.


Assuntos
Neoplasias da Mama , Melanoma , Humanos , Feminino , Neoplasias da Mama/patologia , Transcriptoma , Perfilação da Expressão Gênica , Microambiente Tumoral/genética , Análise de Célula Única
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