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1.
Nat Commun ; 15(1): 3855, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719820

RESUMO

Converting elementary sulfur into sulfur-rich polymers provides a sustainable strategy to replace fossil-fuel-based plastics. However, the low ring strain of eight-membered rings, i.e., S8 monomers, compromises their ring-opening polymerization (ROP) due to lack of an enthalpic driving force and as a consequence, poly(sulfur) is inherently unstable. Here we report that copolymerization with cyclic disulfides, e.g., 1,2-dithiolanes, can enable a simple and energy-saving way to convert elementary sulfur into sulfur-rich thermoplastics. The key strategy is to combine two types of ROP-both mediated by disulfide bond exchange-to tackle the thermodynamic instability of poly(sulfur). Meanwhile, the readily modifiable sidechain of the cyclic disulfides provides chemical space to engineer the mechanical properties and dynamic functions over a large range, e.g., self-repairing ability and degradability. Thus, this simple and robust system is expected to be a starting point for the organic transformation of inorganic sulfur toward sulfur-rich functional and green plastics.

3.
Adv Mater ; : e2403880, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38723049

RESUMO

Classic approaches to integrate flexible capacitive sensor performance are to on-demand microstructing dielectric layers and to adjust dielectric material compositions via the introduction of insoluble carbon additives (to increase sensitivity) or dynamic interactions (to achieve self-healing). However, the sensor's enhanced performances often come with the increased material complexity, discouraging its circular economy. Herein, we introduce a new intrinsic self-healable, closed-loop recyclable dielectric layer material, a fully nature-derived dynamic covalent poly(disulfide) decorated with rich H bonding and metal-catechol complexations. The polymer network possesses a mechanically ductile character with an Arrhenius-like dependent viscoelasticity. The assembled capacitive pressure sensor is able to achieve a sensitivity up to 9.26 kPa-1, fast response/recovery times of 32/24 ms, and could deliver consistent signals of continuous consecutive cycles even after being self-healed or closed-loop recycled for real-time detection of human motions. This is expected to be of high interest for current capacitive sensing research to move towards a life-like, high performance and circular economy direction. This article is protected by copyright. All rights reserved.

4.
Angew Chem Int Ed Engl ; : e202407385, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38736176

RESUMO

Circularly polarized luminescence (CPL) is promising for applications in many fields. However, most systems involving CPL are within the visible range; near‒infrared (NIR) CPL‒active materials, especially those that exhibit high glum values and can be controlled spatially and temporally, are rare. Herein, dynamic NIR‒CPL with a glum value of 2.5[[EQUATION]]10‒2 was achieved through supramolecular coassembly and energy transfer strategies. The chiral assemblies formed by the coassembly between adenosine triphosphate (ATP) and a pyrene derivative exhibit a red CPL signal (glum of 10‒3). The further introduction of sulfo‒cyanine5 resulted in a cooperative energy transfer process, which not only aroused the NIR CPL but also increased the glum value to 10‒2. Temporal control of these chiral assemblies was realized by introducing alkaline phosphatase to fabricate a biomimetic enzyme‒catalyzed network, allowing the dynamic NIR CPL signal to be turned on. Based on these enzyme-regulated temporally controllable dynamic CPL-active chiral assemblies, a multilevel information encryption system was further developed. Our work provides a pioneering example for constructing dynamic NIR CPL materials holding the ability to perform temporal control via the supramolecular assembly strategy, which is expected to aid in the design of supramolecular complex systems that more closely resemble natural biological systems.

5.
Front Microbiol ; 15: 1372078, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605705

RESUMO

Introduction: An unprecedented surge of Omicron infections appeared nationwide in China in December 2022 after the adjustment of the COVID-19 response policy. Here, we report the clinical and genomic characteristics of SARS-CoV-2 infections among children in Shanghai during this outbreak. Methods: A total of 64 children with symptomatic COVID-19 were enrolled. SARS-CoV-2 whole genome sequences were obtained using next-generation sequencing (NGS) technology. Patient demographics and clinical characteristics were compared between variants. Phylogenetic tree, mutation spectrum, and the impact of unique mutations on SARS-CoV-2 proteins were analysed in silico. Results: The genomic monitoring revealed that the emerging BA.5.2.48 and BF.7.14 were the dominant variants. The BA.5.2.48 infections were more frequently observed to experience vomiting/diarrhea and less frequently present cough compared to the BF.7.14 infections among patients without comorbidities in the study. The high-frequency unique non-synonymous mutations were present in BA.5.2.48 (N:Q241K) and BF.7.14 (nsp2:V94L, nsp12:L247F, S:C1243F, ORF7a:H47Y) with respect to their parental lineages. Of these mutations, S:C1243F, nsp12:L247F, and ORF7a:H47Y protein were predicted to have a deleterious effect on the protein function. Besides, nsp2:V94L and nsp12:L247F were predicted to destabilize the proteins. Discussion: Further in vitro to in vivo studies are needed to verify the role of these specific mutations in viral fitness. In addition, continuous genomic monitoring and clinical manifestation assessments of the emerging variants will still be crucial for the effective responses to the ongoing COVID-19 pandemic.

6.
Cell Mol Neurobiol ; 44(1): 39, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649645

RESUMO

Spinal-cord injury (SCI) is a severe condition that can lead to limb paralysis and motor dysfunction, and its pathogenesis is not fully understood. The objective of this study was to characterize the differential gene expression and molecular mechanisms in the spinal cord of mice three days after spinal cord injury. By analyzing RNA sequencing data, we identified differentially expressed genes and discovered that the immune system and various metabolic processes play crucial roles in SCI. Additionally, we identified UHRF1 as a key gene that plays a significant role in SCI and found that SCI can be improved by suppressing UHRF1. These findings provide important insights into the molecular mechanisms of SCI and identify potential therapeutic targets that could greatly contribute to the development of new treatment strategies for SCI.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Traumatismos da Medula Espinal , Ubiquitina-Proteína Ligases , Animais , Traumatismos da Medula Espinal/fisiopatologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Camundongos , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Atividade Motora/fisiologia , Camundongos Endogâmicos C57BL , Recuperação de Função Fisiológica/fisiologia , Feminino , Medula Espinal/metabolismo , Medula Espinal/patologia , Regulação da Expressão Gênica
7.
Mol Neurobiol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662299

RESUMO

Numerous neurological disorders share a fatal pathologic process known as glutamate excitotoxicity. Among which, ischemic stroke is the major cause of mortality and disability worldwide. For a long time, the main idea of developing anti-excitotoxic neuroprotective agents was to block glutamate receptors. Despite this, there has been little successful clinical translation to date. After decades of "neuron-centered" views, a growing number of studies have recently revealed the importance of non-neuronal cells. Glial cells, cerebral microvascular endothelial cells, blood cells, and so forth are extensively engaged in glutamate synthesis, release, reuptake, and metabolism. They also express functional glutamate receptors and can listen and respond for fast synaptic transmission. This broadens the thoughts of developing excitotoxicity antagonists. In this review, the critical contribution of non-neuronal cells in glutamate excitotoxicity during ischemic stroke will be emphasized in detail, and the latest research progress as well as corresponding therapeutic strategies will be updated at length, aiming to reconceptualize glutamate excitotoxicity in a non-neuronal perspective.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38683903

RESUMO

Graphene is a promising material for thermoacoustic sources due to its extremely low heat capacity per unit area and high thermal conductivity. However, current graphene thermoacoustic devices have limited device area and relatively high cost, which limit their applications of daily use. Here, we adopt a dip-coating method to fabricate a large-scale and cost-effective graphene sound source. This sound source has the three-dimensional (3D) porous structure that can increase the contact area between graphene and air, thus assisting heat to release into the air. In this method, polyurethane (PU) is used as a support, and graphene nanoplates are attached onto the PU skeleton so that a highly flexible graphene foam (GrF) device is obtained. At a measuring distance of 1 mm, it can emit sound at up to 70 dB under the normalized input power of 1 W. Considering its unique porous structure, we establish a thermoacoustic analysis model to simulate the acoustic performance of GrF. Furthermore, the obtained GrF can be made up to 44 in. (100 cm × 50 cm) in size, and it has good flexibility and processability, which broadens the application fields of GrF loudspeakers. It can be attached to the surfaces of objects with different shapes, making it suitable to be used as a large-area speaker in automobiles, houses, and other application scenarios, such as neck mounted speaker. In addition, it can also be widely used as a fully flexible in-ear earphone.

9.
Small ; : e2400240, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593333

RESUMO

In this work, Pt3Fe nanoparticles (Pt3Fe NPs) with the ordered internal structure and Pt-rich shells surrounded by plenty of Fe single atoms (Fe SAs) as active species (Pt3Fe NP-in-Fe SA) loaded in the carbon materials are successfully fabricated, which are abbreviated as island-in-sea structured (IISS) Pt3Fe NP-in-Fe SA catalysts. Moreover, the synergistic effect of O-bridging between Pt3Fe NPs and Fe SAs, and the ordered internal structured Pt3Fe NPs with Pt-rich shells of an optimal thickness contributes to the achievement of the local acidic environments on the surfaces of Pt3Fe NPs in the alkaline hydrogen evolution reaction (HER) and the enhancement of the desorption rate of *OH intermediate in the acidic oxygen reduction reaction (ORR). In addition, the electronic interactions between Pt3Fe NPs and dispersed Fe SAs cannot only provide efficient electrons transfer, but also prevent the aggregation and dissolution of Pt3Fe NPs. Furthermore, the overpotential and the half wave potential of the as-prepared IISS Pt3Fe NP-in-Fe SA catalysts toward the alkaline HER and toward the acidic ORR are 8 mV at a current density of 10 mA cm-2 and 0.933 V, respectively, which is 29 lower and 86 mV higher than those (37 mV and 0.847 V) of commercial Pt/C catalysts.

10.
Food Chem ; 449: 139197, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581788

RESUMO

Abalone (Haliotis spp.) is a shellfish known for its exceptional nutritional value and significant economic worth. This study investigated the dynamic characteristics of non-volatile compounds over a year, including metabolites, lipids, nucleotides, and free amino acids (FAAs), which determined the nutritional quality and flavor of abalone. 174 metabolites and 371 lipids were identified and characterized, while 20 FAAs and 11 nucleotides were quantitatively assessed. These non-volatile compounds of abalone were fluctuated with months variation, which was consistent with the fluctuations of environmental factors, especially seawater temperature. Compared with seasonal variation, gender had less influence on these non-volatiles. June and July proved to be the optimal harvesting periods for abalone, with the levels of overall metabolites, lipids, FAAs, and nucleotides in abalone exhibiting a higher value in June and July over a year. Intriguingly, taurine covered 60% of the total FAAs and abalone could be used as dietary taurine supplementation.


Assuntos
Aminoácidos , Gastrópodes , Metabolômica , Estações do Ano , Frutos do Mar , Animais , Gastrópodes/química , Gastrópodes/metabolismo , Frutos do Mar/análise , Aminoácidos/metabolismo , Aminoácidos/análise , Aminoácidos/química , Lipídeos/química , Valor Nutritivo , Masculino , Feminino
11.
Signal Transduct Target Ther ; 9(1): 61, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38514615

RESUMO

Transforming growth factor (TGF)-ß is a multifunctional cytokine expressed by almost every tissue and cell type. The signal transduction of TGF-ß can stimulate diverse cellular responses and is particularly critical to embryonic development, wound healing, tissue homeostasis, and immune homeostasis in health. The dysfunction of TGF-ß can play key roles in many diseases, and numerous targeted therapies have been developed to rectify its pathogenic activity. In the past decades, a large number of studies on TGF-ß signaling have been carried out, covering a broad spectrum of topics in health, disease, and therapeutics. Thus, a comprehensive overview of TGF-ß signaling is required for a general picture of the studies in this field. In this review, we retrace the research history of TGF-ß and introduce the molecular mechanisms regarding its biosynthesis, activation, and signal transduction. We also provide deep insights into the functions of TGF-ß signaling in physiological conditions as well as in pathological processes. TGF-ß-targeting therapies which have brought fresh hope to the treatment of relevant diseases are highlighted. Through the summary of previous knowledge and recent updates, this review aims to provide a systematic understanding of TGF-ß signaling and to attract more attention and interest to this research area.


Assuntos
Transdução de Sinais , Fator de Crescimento Transformador beta , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Citocinas
12.
ACS Appl Mater Interfaces ; 16(12): 15426-15434, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38497376

RESUMO

High-conducting single-molecule junctions have attracted a great deal of attention, but insulating single-molecule junctions, which are critical in molecular circuits, have been less investigated due to the long-standing challenges. Herein, the in situ formation of a Au-C linker via electrical-potential-mediated sp2 C-H bond metalation of polyfluoroarenes with the assistance of scanning tunneling microscope-based break junction technique is reported. This metalation process is bias-dependent and occurs with an electropositive electrode, and the formed junction is highly oriented. Surprisingly, these polyfluoroarenes exhibit unexpected low conductance even under short molecular lengths and are superior molecular insulators. Flicker noise analysis and DFT calculations confirm that the insulating properties of polyfluoroarenes are ascribed to their multiple fluorine substituents. Our results pave a way for constructing oriented asymmetric molecular junctions and provide an efficient strategy to suppress the single-molecule conductance, which will aid in the design of molecular insulators and advance the development of self-integrating functional molecular circuits.

14.
Food Chem ; 447: 138949, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38484544

RESUMO

Abalone, a highly sought-after aquatic product, possesses significant nutritional value. In this study, the relationship between aroma characteristics and lipid profile of abalone (Haliotis discus hannai) during seasonal fluctuation and thermal processing were profiled via volatolomics and lipidomics. 46 aroma compounds and 371 lipids were identified by HS-SPME-GC-MS and UPLC-Q-Extractive Orbitrap-MS, respectively. Multivariate statistical analysis indicated that carbonyls (aldehydes and ketones) and alcohols were the characteristic aroma compounds of abalone. The fluctuations in the aroma compound and lipid composition of abalone were consistent with the seasonal variation, especially seawater temperature. In addition, based on the correlation analysis, it was found that carbonyls (aldehydes and ketones) and alcohols had a positive correlation with phospholipids (lysophosphatidylethanolamines and lysophosphatidylcholines), while a negative correlation was observed with fatty acyls. These findings suggested that the effect of seasonal variations on the aroma changes of abalone might achieved by modulating the lipids composition of abalone.


Assuntos
Gastrópodes , Odorantes , Animais , Estações do Ano , Fosfolipídeos , Aldeídos , Cetonas
15.
EBioMedicine ; 101: 105019, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364701

RESUMO

BACKGROUND: In recent years, a growing number of patients with multiple primary lung cancer (MPLC) are being diagnosed, and a subset of these patients is found to have a large number of lesions at the time of diagnosis, which are referred to as 'super MPLC'. METHODS: Here, we perform whole exome sequencing (WES) and immunohistochemistry (IHC) analysis of PD-L1 and CD8 on 212 tumor samples from 42 patients with super MPLC. FINDINGS: We report the genomic alteration landscape of super MPLC. EGFR, RBM10 and TP53 mutation and TERT amplification are important molecular events in the evolution of super MPLC. We propose the conception of early intrapulmonary metastasis, which exhibits different clinical features from conventional metastasis. The IHC analyses of PD-L1 and CD8 reveal a less inflamed microenvironment of super MPLC than that of traditional non-small cell lung cancer (NSCLC). We identify the potentially susceptible germline mutations for super MPLC. INTERPRETATION: Our study depicts the genomic characteristics and immune landscape, providing insights into the pathogenesis and possible therapeutic guidance of super MPLC. FUNDING: A full list of funding bodies that supported this study can be found in the Acknowledgements section.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Neoplasias Pulmonares/patologia , Antígeno B7-H1/genética , Mutação , Genômica , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/genética , Microambiente Tumoral/genética , Proteínas de Ligação a RNA/genética
16.
Eur J Pharmacol ; 968: 176368, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316246

RESUMO

Spinal cord injury (SCI) is a traumatic neuropathic condition that results in motor, sensory and autonomic dysfunction. Mitochondrial dysfunction caused by primary trauma is one of the critical pathogenic mechanisms. Moderate levels of zinc have antioxidant effects, promote neurogenesis and immune responses. Zinc normalises mitochondrial morphology in neurons after SCI. However, how zinc protects mitochondria within neurons is unknown. In the study, we used transwell culture, Western blot, Quantitative Real-time Polymerase Chain Reaction (QRT-PCR), ATP content detection, reactive oxygen species (ROS) activity assay, flow cytometry and immunostaining to investigate the relationship between zinc-treated microglia and injured neurons through animal and cell experiments. We found that zinc promotes mitochondrial transfer from microglia to neurons after SCI through Sirtuin 3 (SIRT3) regulation of Mitofusin 2 protein (Mfn2). It can rescue mitochondria in damaged neurons and inhibit oxidative stress, increase ATP levels and promote neuronal survival. Therefore, it can improve the recovery of motor function in SCI mice. In conclusion, our work reveals a potential mechanism to describe the communication between microglia and neurons after SCI, which may provide a new idea for future therapeutic approaches to SCI.


Assuntos
Sirtuína 3 , Traumatismos da Medula Espinal , Camundongos , Animais , Medula Espinal/metabolismo , Sirtuína 3/metabolismo , Zinco/metabolismo , Traumatismos da Medula Espinal/metabolismo , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , GTP Fosfo-Hidrolases/metabolismo
17.
J Org Chem ; 89(5): 3597-3604, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38356389

RESUMO

A very mild and efficient procedure has been developed for the preparation of N-methylated uridine, pseudouridine, guanosine and inosine derivatives. This process was compatible with free hydroxyls within the ribose and did not require precautions on the protection or deprotection of other functionalities. The key to this extremely mild methylation without protection relied on the in situ generated methyl oxonium from the Wittig reagent and methanol. A putative mechanism for the selective methylation was also proposed.

18.
Nanomicro Lett ; 16(1): 119, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363512

RESUMO

Due to the constraints imposed by physical effects and performance degradation, silicon-based chip technology is facing certain limitations in sustaining the advancement of Moore's law. Two-dimensional (2D) materials have emerged as highly promising candidates for the post-Moore era, offering significant potential in domains such as integrated circuits and next-generation computing. Here, in this review, the progress of 2D semiconductors in process engineering and various electronic applications are summarized. A careful introduction of material synthesis, transistor engineering focused on device configuration, dielectric engineering, contact engineering, and material integration are given first. Then 2D transistors for certain electronic applications including digital and analog circuits, heterogeneous integration chips, and sensing circuits are discussed. Moreover, several promising applications (artificial intelligence chips and quantum chips) based on specific mechanism devices are introduced. Finally, the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed, and potential development pathways or roadmaps are further speculated and outlooked.

19.
Nanomicro Lett ; 16(1): 104, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300424

RESUMO

The crossmodal interaction of different senses, which is an important basis for learning and memory in the human brain, is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception, but related researches are scarce. Here, we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus (VP) van der Waals heterojunctions. Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene, the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude, reaching up to 7.7 A W-1. Excited by ultraviolet light, multiple synaptic functions, including excitatory postsynaptic currents, paired-pulse facilitation, short/long-term plasticity and "learning-experience" behavior, were demonstrated with a low power consumption. Furthermore, the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments, enabling it to simulate the interaction of visual and olfactory information for crossmodal perception. This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38199058

RESUMO

Heparin-induced thrombocytopenia (HIT) is an immune complication of heparin therapy. Antibodies binding to complexes of platelet factor 4 (PF4) and heparin is the trigger of HIT. A method using size exclusion chromatography with multi-angle laser light scattering detector (SEC-MALS) was developed in this work. The soluble ultra-large complex (ULC) was separated from the small complex (SC) and their molecular weights (MWs) were firstly measured. The complexes of PF4 and three heparins with different MW, including unfractionated heparin (UFH), dalteparin (Daltep) and enoxaparin (Eno) were characterized using this method. The contents and the sizes of ULC increased gradually when heparins were added to PF4 to certain amounts. While, they reduced after more heparins were added. It is the first time to measure the MWs of the biggest ULC of PF4-heparins as millions of Dalton. at the proper ratios of PF4 to heparin (PHR). Meanwhile, those mixtures at those certain PHRs induced the higher expression of CD83 and CD14 markers on dendritic cells (DCs) suggesting that they had stronger immunogenicity and is critical for HIT.


Assuntos
Heparina , Trombocitopenia , Humanos , Heparina/farmacologia , Fator Plaquetário 4/química , Fator Plaquetário 4/metabolismo , Anticoagulantes/química , Trombocitopenia/induzido quimicamente , Fatores Imunológicos , Cromatografia em Gel
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