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1.
Plant Cell ; 35(7): 2449-2463, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-36943796

RESUMO

Cryptophyte plastids originated from a red algal ancestor through secondary endosymbiosis. Cryptophyte photosystem I (PSI) associates with transmembrane alloxanthin-chlorophyll a/c proteins (ACPIs) as light-harvesting complexes (LHCs). Here, we report the structure of the photosynthetic PSI-ACPI supercomplex from the cryptophyte Chroomonas placoidea at 2.7-Å resolution obtained by crygenic electron microscopy. Cryptophyte PSI-ACPI represents a unique PSI-LHCI intermediate in the evolution from red algal to diatom PSI-LHCI. The PSI-ACPI supercomplex is composed of a monomeric PSI core containing 14 subunits, 12 of which originated in red algae, 1 diatom PsaR homolog, and an additional peptide. The PSI core is surrounded by 14 ACPI subunits that form 2 antenna layers: an inner layer with 11 ACPIs surrounding the PSI core and an outer layer containing 3 ACPIs. A pigment-binding subunit that is not present in any other previously characterized PSI-LHCI complexes, ACPI-S, mediates the association and energy transfer between the outer and inner ACPIs. The extensive pigment network of PSI-ACPI ensures efficient light harvesting, energy transfer, and dissipation. Overall, the PSI-LHCI structure identified in this study provides a framework for delineating the mechanisms of energy transfer in cryptophyte PSI-LHCI and for understanding the evolution of photosynthesis in the red lineage, which occurred via secondary endosymbiosis.


Assuntos
Diatomáceas , Complexos de Proteínas Captadores de Luz , Complexos de Proteínas Captadores de Luz/metabolismo , Clorofila A/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Fotossíntese , Transferência de Energia , Diatomáceas/metabolismo
2.
Plant J ; 119(1): 283-299, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38606500

RESUMO

Drought stress is one of the dominating challenges to the growth and productivity in crop plants. Elucidating the molecular mechanisms of plants responses to drought stress is fundamental to improve fruit quality. However, such molecular mechanisms are poorly understood in apple (Malus domestica Borkh.). In this study, we explored that the BTB-BACK-TAZ protein, MdBT2, negatively modulates the drought tolerance of apple plantlets. Moreover, we identified a novel Homeodomain-leucine zipper (HD-Zip) transcription factor, MdHDZ27, using a yeast two-hybrid (Y2H) screen with MdBT2 as the bait. Overexpression of MdHDZ27 in apple plantlets, calli, and tomato plantlets enhanced their drought tolerance by promoting the expression of drought tolerance-related genes [responsive to dehydration 29A (MdRD29A) and MdRD29B]. Biochemical analyses demonstrated that MdHDZ27 directly binds to and activates the promoters of MdRD29A and MdRD29B. Furthermore, in vitro and in vivo assays indicate that MdBT2 interacts with and ubiquitinates MdHDZ27, via the ubiquitin/26S proteasome pathway. This ubiquitination results in the degradation of MdHDZ27 and weakens the transcriptional activation of MdHDZ27 on MdRD29A and MdRD29B. Finally, a series of transgenic analyses in apple plantlets further clarified the role of the relationship between MdBT2 and MdHDZ27, as well as the effect of their interaction on drought resistance in apple plantlets. Collectively, our findings reveal a novel mechanism by which the MdBT2-MdHDZ27 regulatory module controls drought tolerance, which is of great significance for enhancing the drought resistance of apple and other plants.


Assuntos
Resistência à Seca , Malus , Proteínas de Plantas , Fatores de Transcrição , Ubiquitinação , Resistência à Seca/genética , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
FASEB J ; 38(10): e23679, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38780117

RESUMO

Retinal vascular diseases (RVDs), in particular diabetic retinopathy, retinal vein occlusion, and retinopathy of prematurity, are leading contributors to blindness. The pathogenesis of RVD involves vessel dilatation, leakage, and occlusion; however, the specific underlying mechanisms remain unclear. Recent findings have indicated that pericytes (PCs), as critical members of the vascular mural cells, significantly contribute to the progression of RVDs, including detachment from microvessels, alteration of contractile and secretory properties, and excessive production of the extracellular matrix. Moreover, PCs are believed to have mesenchymal stem properties and, therefore, might contribute to regenerative therapy. Here, we review novel ideas concerning PC characteristics and functions in RVDs and discuss potential therapeutic strategies based on PCs, including the targeting of pathological signals and cell-based regenerative treatments.


Assuntos
Pericitos , Pericitos/metabolismo , Humanos , Animais , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Doenças Retinianas/terapia , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/terapia , Retinopatia Diabética/patologia
4.
Proc Natl Acad Sci U S A ; 119(38): e2207353119, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095218

RESUMO

Radiative thermal management provides a zero-energy strategy to reduce the demands of fossil energy for active thermal management. However, whether solar heating or radiative cooling, one-way temperature control will exacerbate all-season energy consumption during hot summers or cold winters. Inspired by the Himalayan rabbit's hair and Mimosa pudica's leaves, we proposed a dual-mode thermal-management device with two differently selective electromagnetic spectrums. The combination of visible and infrared "thermochromism" enables this device to freely switch between solar heating and radiative cooling modes by spontaneously perceiving the temperature without any external energy consumption. Numerical prediction shows that a dual-mode device exhibits an outstanding potential for all-season energy saving in terms of thermal management beyond most static or single-wavelength, range-regulable, temperature-responsive designs. Such a scalable and cost-efficient device represents a more efficient radiative thermal-management strategy toward applying in a practical scenario with dynamic daily and seasonal variations.

5.
Am J Physiol Cell Physiol ; 327(1): C124-C139, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38766767

RESUMO

Protein synthesis regulation is critical for skeletal muscle hypertrophy, yet other established cellular processes are necessary for growth-related cellular remodeling. Autophagy has a well-acknowledged role in muscle quality control, but evidence for its role in myofiber hypertrophy remains equivocal. Both mammalian target of rapamycin complex I (mTORC1) and bone morphogenetic protein (BMP)-Smad1/5 (Sma and Mad proteins from Caenorhabditis elegans and Drosophila, respectively) signaling are reported regulators of myofiber hypertrophy; however, gaps remain in our understanding of how this regulation is integrated with growth processes and autophagy regulation. Therefore, we investigated the mTORC1 and Smad1/5 regulation of protein synthesis and autophagy flux during serum-stimulated myotube growth. Chronic serum stimulation experiments were performed on day 5 differentiated C2C12 myotubes incubated in differentiation medium [2% horse serum (HS)] or growth medium [5% fetal bovine serum (FBS)] for 48 h. Rapamycin or LDN193189 was dosed for 48 h to inhibit mTORC1 and BMP-Smad1/5 signaling, respectively. Acute serum stimulation was examined in day 7 differentiated myotubes. Protein synthesis was measured by puromycin incorporation. Bafilomycin A1 and immunoblotting for LC3B were used to assess autophagy flux. Chronic serum stimulation increased myotube diameter 22%, total protein 21%, total RNA 100%, and Smad1/5 phosphorylation 404% and suppressed autophagy flux. Rapamycin, but not LDN193189, blocked serum-induced myotube hypertrophy and the increase in total RNA. Acute serum stimulation increased protein synthesis 111%, Smad1/5 phosphorylation 559%, and rpS6 phosphorylation 117% and suppressed autophagy flux. Rapamycin increased autophagy flux during acute serum stimulation. These results provide evidence for mTORC1, but not BMP-Smad1/5, signaling being required for serum-induced myotube hypertrophy and autophagy flux by measuring LC3BII/I expression. Further investigation is warranted to examine the role of autophagy flux in myotube hypertrophy.NEW & NOTEWORTHY The present study demonstrates that myotube hypertrophy caused by chronic serum stimulation requires mammalian target of rapamycin complex 1 (mTORC1) signaling but not bone morphogenetic protein (BMP)-Smad1/5 signaling. The suppression of autophagy flux was associated with serum-induced myotube hypertrophy and mTORC1 regulation of autophagy flux by measuring LC3BII/I expression. Rapamycin is widely investigated for beneficial effects in aging skeletal muscle and sarcopenia; our results provide evidence that rapamycin can regulate autophagy-related signaling during myotube growth, which could benefit skeletal muscle functional and metabolic health.


Assuntos
Autofagia , Hipertrofia , Alvo Mecanístico do Complexo 1 de Rapamicina , Fibras Musculares Esqueléticas , Transdução de Sinais , Animais , Camundongos , Autofagia/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Hipertrofia/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Soro/metabolismo , Proteína Smad1/metabolismo , Proteína Smad1/genética , Proteína Smad5/metabolismo , Proteína Smad5/genética
6.
Diabetologia ; 67(3): 528-546, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127123

RESUMO

AIMS/HYPOTHESIS: Diabetes mellitus is associated with impaired insulin secretion, often aggravated by oversecretion of glucagon. Therapeutic interventions should ideally correct both defects. Glucagon-like peptide 1 (GLP-1) has this capability but exactly how it exerts its glucagonostatic effect remains obscure. Following its release GLP-1 is rapidly degraded from GLP-1(7-36) to GLP-1(9-36). We hypothesised that the metabolite GLP-1(9-36) (previously believed to be biologically inactive) exerts a direct inhibitory effect on glucagon secretion and that this mechanism becomes impaired in diabetes. METHODS: We used a combination of glucagon secretion measurements in mouse and human islets (including islets from donors with type 2 diabetes), total internal reflection fluorescence microscopy imaging of secretory granule dynamics, recordings of cytoplasmic Ca2+ and measurements of protein kinase A activity, immunocytochemistry, in vivo physiology and GTP-binding protein dissociation studies to explore how GLP-1 exerts its inhibitory effect on glucagon secretion and the role of the metabolite GLP-1(9-36). RESULTS: GLP-1(7-36) inhibited glucagon secretion in isolated islets with an IC50 of 2.5 pmol/l. The effect was particularly strong at low glucose concentrations. The degradation product GLP-1(9-36) shared this capacity. GLP-1(9-36) retained its glucagonostatic effects after genetic/pharmacological inactivation of the GLP-1 receptor. GLP-1(9-36) also potently inhibited glucagon secretion evoked by ß-adrenergic stimulation, amino acids and membrane depolarisation. In islet alpha cells, GLP-1(9-36) led to inhibition of Ca2+ entry via voltage-gated Ca2+ channels sensitive to ω-agatoxin, with consequential pertussis-toxin-sensitive depletion of the docked pool of secretory granules, effects that were prevented by the glucagon receptor antagonists REMD2.59 and L-168049. The capacity of GLP-1(9-36) to inhibit glucagon secretion and reduce the number of docked granules was lost in alpha cells from human donors with type 2 diabetes. In vivo, high exogenous concentrations of GLP-1(9-36) (>100 pmol/l) resulted in a small (30%) lowering of circulating glucagon during insulin-induced hypoglycaemia. This effect was abolished by REMD2.59, which promptly increased circulating glucagon by >225% (adjusted for the change in plasma glucose) without affecting pancreatic glucagon content. CONCLUSIONS/INTERPRETATION: We conclude that the GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of glucagon secretion. We propose that the increase in circulating glucagon observed following genetic/pharmacological inactivation of glucagon signalling in mice and in people with type 2 diabetes reflects the removal of GLP-1(9-36)'s glucagonostatic action.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Ilhotas Pancreáticas , Fragmentos de Peptídeos , Humanos , Glucagon/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Ilhotas Pancreáticas/metabolismo , Hipoglicemia/metabolismo , Insulina/metabolismo
7.
Mol Plant Microbe Interact ; 37(5): 477-484, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38377033

RESUMO

Colletotrichum tabacum, causing anthracnose in tobacco, is a notorious plant pathogen threatening tobacco production globally. The underlying mechanisms of C. tabacum effectors that interfere with plant defense are not well known. Here, we identified a novel effector, Cte1, from C. tabacum, and its expression was upregulated in the biotrophic stage. We found that Cte1 depresses plant cell death initiated by BAX and inhibits reactive oxygen species (ROS) bursts triggered by flg22 and chitin in Nicotiana benthamiana. The CTE1 knockout mutants decrease the virulence of C. tabacum to N. benthamiana, and the Cte1 transgenic N. benthamiana increase susceptibility to C. tabacum, verifying that Cte1 is involved in the pathogenicity of C. tabacum. We demonstrated that Cte1 interacted with NbCPR1, a Constitutive expresser of Plant Resistance (CPR) protein in plants. Silencing of NbCPR1 expression attenuated the infection of C. tabacum, indicating that NbCPR1 negatively regulates plant immune responses. Cte1 stabilizes NbCPR1 in N. benthamiana. Our study shows that Cte1 suppresses plant immunity to facilitate C. tabacum infection by intervening in the native function of NbCPR1. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.


Assuntos
Colletotrichum , Proteínas Fúngicas , Nicotiana , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Espécies Reativas de Oxigênio , Colletotrichum/patogenicidade , Nicotiana/microbiologia , Nicotiana/imunologia , Nicotiana/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Virulência , Regulação da Expressão Gênica de Plantas
8.
Ecol Lett ; 27(6): e14457, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38844349

RESUMO

Interspecific competition can hinder populations from evolutionarily adapting to abiotic environments, particularly by reducing population size and niche space; and feedback may arise between competitive ability and evolutionary adaptation. Here we studied populations of two model bacterial species, Escherichia coli and Pseudomonas fluorescens, that evolved in monocultures and cocultures for approximately 2400 generations at three temperatures. The two species showed a reversal in competitive dominance in cocultures along the temperature gradient. Populations from cocultures where they had been competitively dominant showed the same magnitude of fitness gain as those in monocultures. However, competitively inferior populations in cocultures showed limited abiotic adaptation compared with those in monocultures. The inferior populations in cocultures were also more likely to evolve weaker interspecific competitive ability, or go extinct. The possible competitive ability-adaptation feedback may have crucial consequences for population persistence.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Escherichia coli , Pseudomonas fluorescens , Pseudomonas fluorescens/fisiologia , Pseudomonas fluorescens/genética , Escherichia coli/fisiologia , Temperatura
9.
J Am Chem Soc ; 146(18): 12294-12299, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38663863

RESUMO

Herein, we present the discovery and development of the first photoredox-catalyzed alkoxy diazomethylation of alkenes with hypervalent iodine reagents and alcohols. This multicomponent process represents a new disconnection approach to diazo compounds and is featured by a broad scope, mild reaction conditions, and excellent selectivity. Key to the process was the generation of diazomethyl radicals, which engaged alkenes and alcohols in an inter- and intramolecular fashion by a photoredox-catalyzed oxidative radical-polar crossover leading to unexplored ß-alkoxydiazo compounds. The synthetic utility of such diazo compounds was demonstrated with a series of transformations involving C-H, N-H, and O-H insertions as well as in the construction of complex sp3-rich heterocycles.

10.
Biochem Biophys Res Commun ; 720: 150118, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38776757

RESUMO

Tectorigenin (TEC) as a plant extract has the advantage of low side effects on metabolic dysfunction-associated steatohepatitis (MASH) treatment. Our previous study have shown that tRNA-derived RNA fragments (tRFs) associated with autophagy and pyroptosis in MASH, but whether TEC can mitigate MASH through tRFs-mediated mitophagy is not fully understood. This study aims to investigate whether TEC relies on tRFs to adjust the crosstalk of hepatocyte mitophagy with pyroptosis in MASH. Immunofluorescence results of PINK1 and PRKN with MitoTracker Green-labeled mitochondria verified that TEC enhanced mitophagy. Additionally, TEC inhibited pyroptosis, as reflected by the level of GSDME, NLRP3, IL-1ß, and IL-18 decreased after TEC treatment, while the effect of pyroptosis inhibition by TEC was abrogated by Pink1 silencing. We found that the upregulation expression of tRF-3040b caused by MASH was suppressed by TEC. The promotion of mitophagy and the suppression of pyroptosis induced by TEC were abrogated by tRF-3040b mimics. TEC reduced lipid deposition, inflammation, and pyroptosis, and promoted mitophagy in mice, but tRF-3040b agomir inhibited these effects. In summary, our findings provided that TEC significantly reduced the expression of tRF-3040b to enhance mitophagy, thereby inhibiting pyroptosis in MASH. We elucidated a powerful theoretical basis and provided safe and effective potential drugs for MASH with the prevention and treatment.


Assuntos
Regulação para Baixo , Isoflavonas , Camundongos Endogâmicos C57BL , Mitofagia , Piroptose , Piroptose/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Animais , Camundongos , Masculino , Isoflavonas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/genética , Humanos
11.
J Neuroinflammation ; 21(1): 106, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658922

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is a devastating neurological disease causing severe sensorimotor dysfunction and cognitive decline, yet there is no effective treatment strategy to alleviate outcomes of these patients. The Mas axis-mediated neuroprotection is involved in the pathology of various neurological diseases, however, the role of the Mas receptor in the setting of ICH remains to be elucidated. METHODS: C57BL/6 mice were used to establish the ICH model by injection of collagenase into mice striatum. The Mas receptor agonist AVE0991 was administered intranasally (0.9 mg/kg) after ICH. Using a combination of behavioral tests, Western blots, immunofluorescence staining, hematoma volume, brain edema, quantitative-PCR, TUNEL staining, Fluoro-Jade C staining, Nissl staining, and pharmacological methods, we examined the impact of intranasal application of AVE0991 on hematoma absorption and neurological outcomes following ICH and investigated the underlying mechanism. RESULTS: Mas receptor was found to be significantly expressed in activated microglia/macrophages, and the peak expression of Mas receptor in microglia/macrophages was observed at approximately 3-5 days, followed by a subsequent decline. Activation of Mas by AVE0991 post-treatment promoted hematoma absorption, reduced brain edema, and improved both short- and long-term neurological functions in ICH mice. Moreover, AVE0991 treatment effectively attenuated neuronal apoptosis, inhibited neutrophil infiltration, and reduced the release of inflammatory cytokines in perihematomal areas after ICH. Mechanistically, AVE0991 post-treatment significantly promoted the transformation of microglia/macrophages towards an anti-inflammatory, phagocytic, and reparative phenotype, and this functional phenotypic transition of microglia/macrophages by Mas activation was abolished by both Mas inhibitor A779 and Nrf2 inhibitor ML385. Furthermore, hematoma clearance and neuroprotective effects of AVE0991 treatment were reversed after microglia depletion in ICH. CONCLUSIONS: Mas activation can promote hematoma absorption, ameliorate neurological deficits, alleviate neuron apoptosis, reduced neuroinflammation, and regulate the function and phenotype of microglia/macrophages via Akt/Nrf2 signaling pathway after ICH. Thus, intranasal application of Mas agonist ACE0991 may provide promising strategy for clinical treatment of ICH patients.


Assuntos
Hematoma , Acidente Vascular Cerebral Hemorrágico , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G , Recuperação de Função Fisiológica , Animais , Camundongos , Hematoma/tratamento farmacológico , Hematoma/patologia , Hematoma/metabolismo , Masculino , Acidente Vascular Cerebral Hemorrágico/patologia , Acidente Vascular Cerebral Hemorrágico/tratamento farmacológico , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Edema Encefálico/etiologia , Edema Encefálico/metabolismo , Edema Encefálico/tratamento farmacológico , Microglia/efeitos dos fármacos , Microglia/metabolismo
12.
Small ; : e2404890, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148186

RESUMO

Enhancing the phase transition reversibility of electrode materials is an effective strategy to alleviate capacity degradation in the cycling of lithium-ion batteries (LIBs). However, a comprehensive understanding of phase transitions under microscopic electrode dynamics is still lacking. In this paper, the activation polarization is quantified as the potential difference between the applied potential (Uabs) and the zero-charge potential (ZCP) of electrode materials. The polarization potential difference facilitates the phase transition by driving Li-ion adsorption and supplying an electron-rich environment. A novel thermodynamic phase diagram is constructed to characterize the phase transition of the example MoS2 under various Li-ion concentrations and operating voltages using the grand canonic fixed-potential method (FPM). At thermodynamic quasi-equilibrium, the ZCP is close to the Uabs, and thus is used to form the discharge curve in the phase diagram. The voltage plateau is observed within the phase transition region in the simulation, which will disappear as the phase transition reversibility is impaired. The obtained discharge curve and phase transition concentration both closely match the experimental results. Overall, the study provides a theoretical understanding of how polarization affects phase evolution in electrode dynamics, which may provide a guideline to improve battery safety and cycle life.

13.
Small ; : e2401308, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

14.
J Bioenerg Biomembr ; 56(1): 73-85, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37999809

RESUMO

Circular RNA (circRNA) plays multiple roles in the development of esophageal cancer (EC). Herein, we investigate the function of circ_0001944 in EC progression and the related mechanism. Expression of circ_0001944, microRNA-338-5p (miR-338-5p), pyruvate dehydrogenase kinase 1 (PDK1), E-cadherin and N-cadherin was analyzed by quantitative real-time polymerase chain reaction, Western blotting or immunohistochemistry assay. Cell viability, proliferation, apoptosis, invasion and migration were investigated by cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), flow cytometry, transwell invasion and wound-healing assays, respectively. Glucose consumption was detected by Glucose Assay Kit. Lactate production was analyzed by Lactate Assay Kit. ATP/ADP ratio was determined by ADP/ATP ratio Assay Kit. The associations among circ_0001944, miR-338-5p and PDK1 were identified by dual-luciferase reporter and RNA pull-down assays. Xenograft mouse model assay was used to explore the role of circ_0001944 on tumor tumorigenesis in vivo. Circ_0001944 and PDK1 expression were significantly upregulated, while miR-338-5p was downregulated in EC tissues and cells in contrast with normal esophageal tissues and cells. Circ_0001944 knockdown inhibited EC cell proliferation, invasion, migration and glycolysis but induced apoptosis. Meanwhile, circ_0001944 depletion suppressed tumor tumorigenesis in vivo. Mechanistically, circ_0001944 bound to miR-338-5p, and miR-338-5p targeted PDK1. In addition, miR-338-5p inhibitors attenuated circ_0001944 depletion-induced effects in EC cells. The regulation of miR-338-5p on EC progression involved the downregulation of PDK1. Further, circ_0001944 controlled PDK1 expression through miR-338-5p. Circ_0001944 knockdown inhibited EC development and glycolysis by regulating the miR-338-5p/PDK1 pathway, providing a promising target for EC therapy.


Assuntos
Neoplasias Esofágicas , MicroRNAs , Humanos , Animais , Camundongos , Neoplasias Esofágicas/genética , Carcinogênese , Glicólise , Proliferação de Células , Modelos Animais de Doenças , Glucose , Lactatos , Trifosfato de Adenosina , MicroRNAs/genética
15.
Rev Cardiovasc Med ; 25(6): 197, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39076341

RESUMO

Background: Patients with coronary artery disease (CAD) often experience pulmonary ventilation dysfunction following their initial event. However, there is insufficient research exploring the relationship between this dysfunction and CAD prognosis. Methods: To address this gap, a retrospective observational study was conducted involving 3800 CAD patients without prior pulmonary ventilation disease who underwent cardiopulmonary exercise testing (CPET) during hospitalization between November 2015 and September 2021. The primary endpoint was a composite of major adverse cardiovascular events (MACE), such as death, myocardial infarction (MI), repeat revascularization, and stroke. Propensity score matching (PSM) was used to minimize selection bias between the two groups, with a subgroup analysis stratified by smoking status. Results: The results showed that patients were divided into normal (n = 2159) and abnormal (n = 1641) groups based on their pulmonary ventilation function detected by CPET, with 1469 smokers and 2331 non-smokers. The median follow-up duration was 1237 (25-75% interquartile range 695-1596) days. The primary endpoint occurred in 390 patients (10.26%). 1472 patients in each of the two groups were enrolled in the current analysis after PSM, respectively. However, pulmonary function was not associated with MACE before (hazard ratio (HR) 1.20, 95% confidence interval (95% CI) 0.99-1.47; Log-rank p = 0.069) or after PSM (HR 1.07, 95% CI 0.86-1.34; Log-rank p = 0.545) among the entire population. Nonetheless, pulmonary ventilation dysfunction was significantly associated with an increased risk of MACE in smoking patients (HR 1.65, 95% CI 1.25-2.18; p < 0.001) but not in non-smoking patients (HR 0.81, 95% CI 0.60-1.09; p = 0.159). In addition, there was a significant interaction between current smoking status and pulmonary ventilation dysfunction on MACE (p for interaction < 0.001). Conclusions: Pulmonary ventilation dysfunction identified through CPET was independently associated with long-term poor prognosis in smoking patients with CAD but not in the overall population.

16.
Mol Psychiatry ; 28(11): 4853-4866, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37737484

RESUMO

Exposure to preadult environmental exposures may have long-lasting effects on mental health by affecting the maturation of the brain and personality, two traits that interact throughout the developmental process. However, environment-brain-personality covariation patterns and their mediation relationships remain unclear. In 4297 healthy participants (aged 18-30 years), we combined sparse multiple canonical correlation analysis with independent component analysis to identify the three-way covariation patterns of 59 preadult environmental exposures, 760 adult brain imaging phenotypes, and five personality traits, and found two robust environment-brain-personality covariation models with sex specificity. One model linked greater stress and less support to weaker functional connectivity and activity in the default mode network, stronger activity in subcortical nuclei, greater thickness and volume in the occipital, parietal and temporal cortices, and lower agreeableness, consciousness and extraversion as well as higher neuroticism. The other model linked higher urbanicity and better socioeconomic status to stronger functional connectivity and activity in the sensorimotor network, smaller volume and surface area and weaker functional connectivity and activity in the medial prefrontal cortex, lower white matter integrity, and higher openness to experience. We also conducted mediation analyses to explore the potential bidirectional mediation relationships between adult brain imaging phenotypes and personality traits with the influence of preadult environmental exposures and found both environment-brain-personality and environment-personality-brain pathways. We finally performed moderated mediation analyses to test the potential interactions between macro- and microenvironmental exposures and found that one category of exposure moderated the mediation pathways of another category of exposure. These results improve our understanding of the effects of preadult environmental exposures on the adult brain and personality traits and may facilitate the design of targeted interventions to improve mental health by reducing the impact of adverse environmental exposures.


Assuntos
Encéfalo , Personalidade , Adulto , Humanos , Neuroticismo , Mapeamento Encefálico , Exposição Ambiental
17.
Connect Tissue Res ; : 1-10, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140391

RESUMO

PURPOSE: Joint contracture is a common disease in clinical practice, joint bleeding is an important factor affecting the progression of joint contracture. This study aimed to explore the effect of extracorporeal shock wave on alleviating joint capsule fibrosis caused by intra-articular hemorrhage in rats. METHODS: Forty two SD rats were randomly divided into seven groups. Perform simple fixation and fixation after blood injection separately. Measure the range of motion of each group's knee joints and calculate the corresponding degree of contraction. Use HE staining and Masson staining to detect the number of anterior joint capsule cells and collagen deposition. Detection of changes in Wnt1, ß-catenin protein expression in joint capsule using Western blotting. RESULTS: Compared to group C, the degree of knee joint contracture in M1 and M2 groups of rats increased, and collagen deposition, cell number and Wnt1, ß-catenin protein expression also increased accordingly. Compared to M1 and M2 groups, the degree of knee contraction in E1 and E2 groups were reduced, while collagen deposition, cell number and Wnt1, ß-catenin protein expression were decreased, and the degree of joint contracture in NR1 and NR2 groups showed no significant improvement. Compared to NR1 and NR2 groups, the degree of knee contraction in E1 and E2 groups were reduced, while collagen deposition, cell number and Wnt1, ß-catenin protein expression were decreased. CONCLUSIONS: Both rat models of knee joint contracture were successful, and joint bleeding can exacerbate joint contracture. Extracorporeal shock waves alleviate joint capsule fibrosis caused by intra-articular bleeding in rats.

18.
Environ Sci Technol ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38323904

RESUMO

Neonicotinoid insecticides (neonics) are extensively employed in agriculture and pervade various environmental matrices. However, few studies have documented the occurrence and potential chronic ecological risks of these chemicals in the marine environment. We collected 720 seawater samples from Xiangshan Bay during 2015-2019 and the integrated concentrations of seven neonics were determined using the relative potency factor method. Trend analyses using the Mann-Kendall test in time series, along with the estimation of the flux of neonics into the sea, were conducted. At last, the ecological risk of neonics was evaluated by water quality criteria derivation based on species sensitivity distribution. Our findings revealed that 47.6% of samples contained at least one neonic, with the integrated concentration of neonics ranging from 63.30 to 1684.14 ng/L. Imidacloprid and dinotefuran exhibited the highest frequency of detection in the analysis. The significance level of the Mann-Kendall test ranged from 2.16 × 10-10 to 1.21 × 10-5 (S > 0), indicating all neonics behaved with sharply increasing trends. Approximately 8.47 × 10-2 tons of neonics were discharged into Xiangshan Bay. Notably, the integrated concentrations of neonics represented a potential chronic ecological risk to marine organisms. This study provided novel insights into the spatial distribution, source, and migration of neonic species and their impacts on marine ecosystems.

19.
Environ Sci Technol ; 58(10): 4545-4557, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38386019

RESUMO

Global warming has caused the degradation of coral reefs around the world. While stress-tolerant corals have demonstrated the ability to acclimatize to ocean warming, it remains unclear whether they can sustain their thermal resilience when superimposed with other coastal environmental stressors. We report the combined impacts of a photosystem II (PSII) herbicide, prometryn, and ocean warming on the stress-tolerant coral Galaxea fascicularis through physiological and omics analyses. The results demonstrate that the heat-stress-induced inhibition of photosynthetic efficiency in G. fascicularis is exacerbated in the presence of prometryn. Transcriptomics and metabolomics analyses indicate that the prometryn exposure may overwhelm the photosystem repair mechanism in stress-tolerant corals, thereby compromising their capacity for thermal acclimation. Moreover, prometryn might amplify the adverse effects of heat stress on key energy and nutrient metabolism pathways and induce a stronger response to oxidative stress in stress-tolerant corals. The findings indicate that the presence of prometryn at environmentally relevant concentrations would render corals more susceptible to heat stress and exacerbate the breakdown of coral Symbiodiniaceae symbiosis. The present study provides valuable insights into the necessity of prioritizing PSII herbicide pollution reduction in coral reef protection efforts while mitigating the effects of climate change.


Assuntos
Antozoários , Herbicidas , Animais , Antozoários/fisiologia , Prometrina , Recifes de Corais , Oceanos e Mares , Simbiose
20.
Phys Chem Chem Phys ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145725

RESUMO

Enhanced dielectric constant and high breakdown strength offers immense promise for excellent energy storage performance, which is of critical significance in modern electronics and power systems. However, polymer nanocomposites with traditional routes have to balance between dielectric constant and breakdown strength, hence hindering substantive increases in energy density. Herein, a sandwiched polymer nanocomposite film has been constructed to take full advantage of the individual component layers. BaTiO3 nanoparticles are coated with a fluoropolymer to form core-shell structures and then introduced into a polymer as the top and the bottom layers of a sandwich film for enhancing polarization. Moreover, boron nitride nanosheets (BNNSs) in the middle layer of the sandwich film exert positive effects on the inhibition of current leakage for high breakdown resistance. The breakdown strength increases from 480 MV m-1 of the neat polymer to 580 MV m-1 of the sandwiched film. Additionally, the film exhibits a higher dielectric constant in comparison with the neat polymer. The sandwiched film displays a superior energy density (15.75 J cm-3), which is about 1.9 times that of the neat polymer. This work proposes a feasible route to achieve excellent energy storage of polymer dielectrics by synergistically introducing insulating fillers and additional dipoles in a sandwiched polymer nanocomposite film.

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