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1.
Nat Commun ; 15(1): 5736, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982049

RESUMO

Excessive exercise is an etiological factor of intervertebral disc degeneration (IVDD). Engineered extracellular vesicles (EVs) exhibit excellent therapeutic potential for disease-modifying treatments. Herein, we fabricate an exercise self-powered triboelectric-responsive microneedle (MN) assay with the sustainable release of optogenetically engineered EVs for IVDD repair. Mechanically, exercise promotes cytosolic DNA sensing-mediated inflammatory activation in senescent nucleus pulposus (NP) cells (the master cell population for IVD homeostasis maintenance), which accelerates IVDD. TREX1 serves as a crucial nuclease, and disassembly of TRAM1-TREX1 complex disrupts the subcellular localization of TREX1, triggering TREX1-dependent genomic DNA damage during NP cell senescence. Optogenetically engineered EVs deliver TRAM1 protein into senescent NP cells, which effectively reconstructs the elimination function of TREX1. Triboelectric nanogenerator (TENG) harvests mechanical energy and triggers the controllable release of engineered EVs. Notably, an optogenetically engineered EV-based targeting treatment strategy is used for the treatment of IVDD, showing promising clinical potential for the treatment of degeneration-associated disorders.


Assuntos
Vesículas Extracelulares , Degeneração do Disco Intervertebral , Agulhas , Núcleo Pulposo , Optogenética , Degeneração do Disco Intervertebral/terapia , Degeneração do Disco Intervertebral/metabolismo , Vesículas Extracelulares/metabolismo , Animais , Núcleo Pulposo/metabolismo , Optogenética/métodos , Optogenética/instrumentação , Humanos , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Senescência Celular , Exodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , Ratos , Dano ao DNA , Camundongos , Masculino , Modelos Animais de Doenças , Ratos Sprague-Dawley
2.
Adv Mater ; : e2406235, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007254

RESUMO

The great challenges for existing wearable pressure sensors are the degradation of sensing performance and weak interfacial adhesion owing to the low mechanical transfer efficiency and interfacial differences at the skin-sensor interface. Here, an ultrasensitive wearable pressure sensor is reported by introducing a stress-concentrated tip-array design and self-adhesive interface for improving the detection limit. A bipyramidal microstructure with various Young's moduli is designed to improve mechanical transfer efficiency from 72.6% to 98.4%. By increasing the difference in modulus, it also mechanically amplifies the sensitivity to 8.5 V kPa-1 with a detection limit of 0.14 Pa. The self-adhesive hydrogel is developed to strengthen the sensor-skin interface, which allows stable signals for long-term and real-time monitoring. It enables generating high signal-to-noise ratios and multifeatures when wirelessly monitoring weak pulse signals and eye muscle movements. Finally, combined with a deep learning bimodal fused network, the accuracy of fatigued driving identification is significantly increased to 95.6%.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38875084

RESUMO

The rapid development of large language models (LLMs), such as ChatGPT, has revolutionized the efficiency of creating programming tutorials. LLMs can be instructed with text prompts to generate comprehensive text descriptions for code snippets provided by users. However, the lack of transparency in the end-to-end generation process has hindered the understanding of model behavior and limited user control over the generated results. To tackle this challenge, we introduce a novel approach that breaks down the programming tutorial creation task into actionable steps. By employing the tree-of-thought method, LLMs engage in an exploratory process to generate diverse and faithful programming tutorials. We then present SPROUT, an authoring tool equipped with a series of interactive visualizations that empower users to have greater control and understanding of the programming tutorial creation process. A formal user study demonstrated the effectiveness of SPROUT, showing that our tool assists users to actively participate in the programming tutorial creation process, leading to more reliable and customizable results. By providing users with greater control and understanding, SPROUT enhances the user experience and improves the overall quality of programming tutorial.A free copy of this paper and all supplemental materials are available at https://osf.io/uez2t/?view only = 5102e958802341daa414707646428f86.

4.
ACS Nano ; 18(26): 17041-17052, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38904995

RESUMO

Flexible tactile sensors show promise for artificial intelligence applications due to their biological adaptability and rapid signal perception. Triboelectric sensors enable active dynamic tactile sensing, while integrating static pressure sensing and real-time multichannel signal transmission is key for further development. Here, we propose an integrated structure combining a capacitive sensor for static spatiotemporal mapping and a triboelectric sensor for dynamic tactile recognition. A liquid metal-based flexible dual-mode triboelectric-capacitive-coupled tactile sensor (TCTS) array of 4 × 4 pixels achieves a spatial resolution of 7 mm, exhibiting a pressure detection limit of 0.8 Pa and a fast response of 6 ms. Furthermore, neuromorphic computing using the MXene-based synaptic transistor achieves 100% recognition accuracy of handwritten numbers/letters within 90 epochs based on dynamic triboelectric signals collected by the TCTS array, and cross-spatial information communication from the perceived multichannel tactile data is realized in the mixed reality space. The results illuminate considerable application possibilities of dual-mode tactile sensing technology in human-machine interfaces and advanced robotics.

5.
Chem Commun (Camb) ; 60(44): 5735-5738, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38742637

RESUMO

Electroreductive ring-opening carboxylation of styrene carbonates with CO2 to achieve dicarboxylic acids and/or ß-hydroxy acids has been developed via the selective cleavage of the C(sp3)-O bond in cyclic carbonates. The product selectivity is probably determined by the stability and reactivity of the key benzylic radical and carbanion intermediate.

6.
ACS Appl Mater Interfaces ; 16(20): 26537-26546, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739859

RESUMO

Water-stable organic radicals are promising photothermal conversion candidates for photothermal therapy (PTT). However, organic radicals are usually unstable in biological environments, which greatly hinders their wide application. Here, we have developed a chaotropic effect-based and photoinduced water-stable supramolecular radical (MB12-2) for efficient antibacterial PTT. The supramolecular radical precursor MB12-1 was constructed by the chaotropic effect between closo-dodecaborate cluster (B12H122-) and N,N'-dimethylated dipyridinium thiazolo [5,4-d] thiazole (MPT2+). Subsequently, with triethanolamine (TEOA) serving as an electron donor, MB12-1 could transform to its radical form MB12-2 through photoinduced electron transfer (PET) under 435-nm laser irradiation. The N2 adsorption-desorption analysis confirmed that MB12-2 was tightly packed through the introduction of B12H122-, which effectively enhanced its stability via a spatial site-blocked effect. Moreover, the half-life of MB12-2 in water was calculated through ultraviolet-visible light (UV-vis) absorption spectra results for periods as long as 20 days. In addition, in the skin infection model, MB12-2, as a wound dressing, showed remarkable photothermal antibacterial activity (>97%) under 660-nm laser irradiation and promoted wound healing. This study presents a simple method for designing long-term water-stable supramolecular radicals, offering a novel avenue for noncontact treatments for bacterial infections.


Assuntos
Antibacterianos , Terapia Fototérmica , Antibacterianos/química , Antibacterianos/farmacologia , Animais , Água/química , Camundongos , Radicais Livres/química , Boro/química , Boro/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos
7.
BMC Vet Res ; 20(1): 147, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643185

RESUMO

BACKGROUND: Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we sought to determine the pharmacokinetic profiles, antimicrobial activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with therapeutic effect of gamithromycin against Pasteurella multocida in rabbits. RESULTS: Gamithromycin showed favorable PK properties in rabbits, including high subcutaneous bioavailability (86.7 ± 10.7%) and low plasma protein binding (18.5-31.9%). PK analysis identified a mean plasma peak concentration (Cmax) of 1.64 ± 0.86 mg/L and terminal half-life (T1/2) of 31.5 ± 5.74 h after subcutaneous injection. For P. multocida, short post-antibiotic effects (PAE) (1.1-5.3 h) and post-antibiotic sub-inhibitory concentration effects (PA-SME) (6.6-9.1 h) were observed after exposure to gamithromycin at 1 to 4× minimal inhibitory concentration (MIC). Gamithromycin demonstrated concentration-dependent bactericidal activity and the PK/PD index area under the concentration-time curve over 24 h (AUC24h)/MIC correlated well with efficacy (R2 > 0.99). The plasma AUC24h/MIC ratios of gamithromycin associated with the bacteriostatic, bactericidal and bacterial eradication against P. multocida were 15.4, 24.9 and 27.8 h in rabbits, respectively. CONCLUSIONS: Subcutaneous administration of 6 mg/kg gamithromycin reached therapeutic concentrations in rabbit plasma against P. multocida. The PK/PD ratios determined herein in combination with ex vivo activity and favorable rabbit PK indicate that gamithromycin may be used for the treatment of rabbit pasteurellosis.


Assuntos
Doenças dos Bovinos , Lagomorpha , Infecções por Pasteurella , Pasteurella multocida , Doenças dos Suínos , Coelhos , Animais , Bovinos , Suínos , Antibacterianos/uso terapêutico , Antibacterianos/farmacocinética , Infecções por Pasteurella/tratamento farmacológico , Infecções por Pasteurella/veterinária , Infecções por Pasteurella/microbiologia , Macrolídeos/uso terapêutico , Macrolídeos/farmacocinética , Testes de Sensibilidade Microbiana/veterinária , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Suínos/tratamento farmacológico
8.
Nano Lett ; 24(15): 4649-4657, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38572971

RESUMO

Deep-seated bacterial infections (DBIs) are stubborn and deeply penetrate tissues. Eliminating deep-seated bacteria and promoting tissue regeneration remain great challenges. Here, a novel radical-containing hydrogel (SFT-B Gel) cross-linked by a chaotropic effect was designed for the sensing of DBIs and near-infrared photothermal therapy (NIR-II PTT). A silk fibroin solution stained with 4,4',4″-(1,3,5-triazine-2,4,6-triyl)tris(1-methylpyridin-1-ium) (TPT3+) was employed as the backbone, which could be cross-linked by a closo-dodecaborate cluster (B12H122-) through a chaotropic effect to form the SFT-B Gel. More interestingly, the SFT-B Gel exhibited the ability to sense DBIs, which could generate a TPT2+• radical with obvious color changes in the presence of bacteria. The radical-containing SFT-B Gel (SFT-B★ Gel) possessed strong NIR-II absorption and a remarkable photothermal effect, thus demonstrating excellent NIR-II PTT antibacterial activity for the treatment of DBIs. This work provides a new approach for the construction of intelligent hydrogels with unique properties using a chaotropic effect.


Assuntos
Fototerapia , Terapia Fototérmica , Hidrogéis/farmacologia
9.
Risk Manag Healthc Policy ; 17: 843-853, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617594

RESUMO

Purpose: The purpose of the study was to determine the status of spiritual needs and influencing factors of postoperative breast cancer (BC) women undergoing chemotherapy. Participants and Methods: This study is a cross-sectional study. A total of 173 participants completed a general information questionnaire and a Chinese version of the Spiritual Needs Scale at the Guangxi Medical University Cancer Hospital. Data were collected by purposive sampling from December 2022 to April 2023. Data were analyzed by descriptive statistics, independent t-test, ANOVA, non-parametric test, and logistic regression analysis. Results: The spiritual needs of postoperative BC women undergoing chemotherapy were at a high level (84.20 ± 12.86). The need for "hope and peace" was considered paramount and the need for a "relationship with transcendence" was considered the least important. Significant differences were found in the following: spiritual needs total score (P=0.040) and "hope and peace" (P=0.021) in education level; "love and connection" in disease stage (P=0.021); "meaning and purpose" in education level (P=0.013), household income (P=0.012), and payment method (P=0.015); "relationship with transcendence" in religion (P<0.001); and "acceptance of dying" in marital status (P=0.023). The level of education was the influencing factor of spiritual needs (OR=1.50, P=0.005), especially for "hope and peace" (OR=1.50, P=0.012). Conclusion: The spiritual need of postoperative BC Chinese women undergoing chemotherapy is at a high level and should receive more attention. In clinical work, nurses should fully assess the spiritual needs of patients and meet their specific needs. Results may help nurses to develop targeted and comprehensive spiritual intervention strategies according to the characteristics of patients.

10.
Theranostics ; 14(6): 2544-2559, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646641

RESUMO

Background: Mechanical forces are indispensable for bone healing, disruption of which is recognized as a contributing cause to nonunion or delayed union. However, the underlying mechanism of mechanical regulation of fracture healing is elusive. Methods: We used the lineage-tracing mouse model, conditional knockout depletion mouse model, hindlimb unloading model and single-cell RNA sequencing to analyze the crucial roles of mechanosensitive protein polycystin-1 (PC1, Pkd1) promotes periosteal stem/progenitor cells (PSPCs) osteochondral differentiation in fracture healing. Results: Our results showed that cathepsin (Ctsk)-positive PSPCs are fracture-responsive and mechanosensitive and can differentiate into osteoblasts and chondrocytes during fracture repair. We found that polycystin-1 declines markedly in PSPCs with mechanical unloading while increasing in response to mechanical stimulus. Mice with conditional depletion of Pkd1 in Ctsk+ PSPCs show impaired osteochondrogenesis, reduced cortical bone formation, delayed fracture healing, and diminished responsiveness to mechanical unloading. Mechanistically, PC1 facilitates nuclear translocation of transcriptional coactivator TAZ via PC1 C-terminal tail cleavage, enhancing osteochondral differentiation potential of PSPCs. Pharmacological intervention of the PC1-TAZ axis and promotion of TAZ nuclear translocation using Zinc01442821 enhances fracture healing and alleviates delayed union or nonunion induced by mechanical unloading. Conclusion: Our study reveals that Ctsk+ PSPCs within the callus can sense mechanical forces through the PC1-TAZ axis, targeting which represents great therapeutic potential for delayed fracture union or nonunion.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Diferenciação Celular , Condrócitos , Consolidação da Fratura , Osteogênese , Células-Tronco , Canais de Cátion TRPP , Animais , Consolidação da Fratura/fisiologia , Camundongos , Canais de Cátion TRPP/metabolismo , Canais de Cátion TRPP/genética , Condrócitos/metabolismo , Células-Tronco/metabolismo , Osteogênese/fisiologia , Camundongos Knockout , Condrogênese/fisiologia , Periósteo/metabolismo , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Modelos Animais de Doenças , Masculino
11.
Sheng Li Xue Bao ; 76(2): 319-328, 2024 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-38658380

RESUMO

Liver cancer is a common tumor of digestive system. Hepatocellular carcinoma (HCC) is a common type of liver cancer, which has a high degree of malignancy and ranks among the top causes of cancer-related death in the world. Metabolic reprogramming is considered to be an important marker of carcinogenesis. Glucose metabolism is one of the main ways for cells to produce energy. Glycolysis, as the basic reaction of glucose metabolism, plays an important role in cell metabolism. Therefore, the regulation of glycolysis is of great significance to the proliferation and evolution of tumors. More and more non-coding RNAs (ncRNA) have been proved to play an important role in the regulation of tumor glycolysis. This article reviews the role of ncRNA in the regulation of HCC glycolysis and its related mechanisms. At the same time, the prospect of targeted therapy for HCC based on the related mechanisms of glycolysis regulation is put forward.


Assuntos
Carcinoma Hepatocelular , Glicólise , Neoplasias Hepáticas , RNA não Traduzido , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais
12.
Ann Med Surg (Lond) ; 86(3): 1590-1600, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463086

RESUMO

Background: Playing an exemplary role, frailty have crucial effect on the preoperative evaluation of elderly patients. Previous studies have shown that frailty is associated with complications and mortality in patients with gastric cancer (GC). However, with the development of the concept of "patient-centered", the range of health-related outcomes is broad. The differences in relation between frailty and various adverse outcomes will be further explored. Method: The PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wan Fang, and Chinese Biomedical Literature databases were searched for keywords, including frailty (such as frail) and gastric cancer (such as stomach neoplasms or stomach cancer or gastrectomy or gastric surgery). The search period is until August 2023. The included studies were observational or cohort studies with postoperative related adverse outcomes as primary or secondary outcome measures. Valid assessment tools were used. The Quality Assessment Tool for Observational Cohort and Cross-sectional Studies was used to assess methodological quality in the included literature. Result: Fifteen studies were included, including 4 cross-sectional studies, 8 retrospective cohort studies, and 3 prospective cohort studies. Among them, 6 studies were rated as "Good" and 9 studies were rated as "Fair," indicating that the quality of the literature was high. Then, 10 frailty assessment tools were summarized and classified into two broad categories in accordance with frailty models. Results of the included studies indicated that frailty in elderly patients with GC was associated with postoperative complications, mortality, hospital days, readmissions, quality of life, non-home discharge, and admission to the intensive care unit. Conclusion: This scoping review concludes that high levels of preoperative frailty increase the risk of adverse outcomes in elderly patients with GC. Frailty will be widely used in the future clinical evaluation of elderly gastric cancer patients, precise risk stratification should be implemented for patients, and frailty management should be implemented well to reduce the occurrence of adverse treatment outcomes.

14.
Adv Healthc Mater ; 13(16): e2303474, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38458151

RESUMO

Electrotherapy is of great interest in the field of tissue repair as an effective, well-tolerated, and noninvasive treatment. Triboelectric nanogenerator (TENG) has shown advantages in promoting wound healing due to its peak output characteristic and low Joule heating effect. However, it is limited in infected wound healing due to poor antimicrobial capacity. Here, a wearable triboelectric stimulator (WTS) is developed that consists of a flexible TENG (F-TENG) and a triboelectric-responsive drug delivery hydrogel (TR-DDH) for healing of bacterium-infected wounds. F-TENG can generate pulsed current to wounds by converting mechanical energy from body movements. Polypyrrole is prone to reduction and volume contraction under electrical stimulation, resulting in desorption of curcumin nanoparticles (CUR NPs) from the polypyrrole in TR-DDH. Therefore, the highly efficient and controllable release of CUR NPs can be achieved by triboelectric stimulation. According to the in vitro and in vivo experiments, WTS has the greatest antimicrobial effect and the fastest promotion of infected wound healing compared to treatment with electrical stimulation or curcumin. Finally, the safety assessment demonstrates that the WTS has excellent tissue safety for chronic wound healing. Synergistic therapy with WTS provides an efficient strategy for chronic wound healing and smart-responsive drug delivery systems.


Assuntos
Curcumina , Sistemas de Liberação de Medicamentos , Hidrogéis , Pirróis , Cicatrização , Cicatrização/efeitos dos fármacos , Curcumina/química , Curcumina/farmacologia , Hidrogéis/química , Animais , Sistemas de Liberação de Medicamentos/métodos , Pirróis/química , Polímeros/química , Nanopartículas/química , Camundongos , Terapia por Estimulação Elétrica/métodos , Dispositivos Eletrônicos Vestíveis , Humanos , Antibacterianos/química , Antibacterianos/farmacologia , Masculino
15.
J Org Chem ; 89(7): 5200-5206, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38500359

RESUMO

A regiodivergent allylation of 1H-indoles highly selectively at the C3 and N1 positions with ß-acyl allylic sulfides through desulfurative C-C/C-N bond-forming reactions has been developed under mild conditions. Notably, the remarkable site-selective switch can be achieved by a delicate choice of solvents and bases. This cost-efficient method displays a broad substrate scope, good functional compatibility, and excellent site-selectivity, thus offering a divergent synthesis of indole substituted α-branched enones, which possess diverse potential opportunities for further applications and derivatization.

16.
Proc Natl Acad Sci U S A ; 121(14): e2318391121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527207

RESUMO

The exploitation of novel wound healing methods with real-time infection sensing and high spatiotemporal precision is highly important for human health. Pt-based metal-organic cycles/cages (MOCs) have been employed as multifunctional antibacterial agents due to their superior Pt-related therapeutic efficiency, various functional subunits and specific geometries. However, how to rationally apply these nanoscale MOCs on the macroscale with controllable therapeutic output is still challenging. Here, a centimeter-scale Pt MOC film was constructed via multistage assembly and subsequently coated on a N,N'-dimethylated dipyridinium thiazolo[5,4-d]thiazole (MPT)-stained silk fabric to form a smart wound dressing for bacterial sensing and wound healing. The MPT on silk fabric could be used to monitor wound infection in real-time through the bacteria-mediated reduction of MPT to its radical form via a color change. The MPT radical also exhibited an excellent photothermal effect under 660 nm light irradiation, which could not only be applied for photothermal therapy but also induce the disassembly of the Pt MOC film suprastructure. The highly ordered Pt MOC film suprastructure exhibited high biosafety, while it also showed improved antibacterial efficiency after thermally induced disassembly. In vitro and in vivo studies revealed that the combination of the Pt MOC film and MPT-stained silk can provide real-time information on wound infection for timely treatment through noninvasive techniques. This study paves the way for bacterial sensing and wound healing with centimeter-scale metal-organic materials.


Assuntos
Platina , Infecção dos Ferimentos , Humanos , Platina/farmacologia , Cicatrização , Bandagens , Antibacterianos/farmacologia , Antibacterianos/química , Seda/química , Bactérias , Hidrogéis/farmacologia
17.
Polymers (Basel) ; 16(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38399918

RESUMO

Aniline compounds, as a class of widely used but highly toxic chemical raw materials, are increasingly being released and accumulated in the environment, posing serious threats to environmental safety and human health. Therefore, developing detection methods for aniline compounds is of particular significance. Herein, we synthesized the fluorescent third monomer cyano-stilbene epoxide M and ternary copolymerized it with carbon dioxide (CO2) and propylene oxide (PO) to synthesize carbon dioxide-based polycarbonate (PPCM) with fluorescence recognition functions, as well as excellent performance, for the first time. The results revealed that the PPCM fluorescent probe exhibited typical aggregation-induced luminescence properties and could be quenched by aniline compounds. The probe presented anti-interference-specific selectivity for aniline compounds, and the detection limit was 1.69 × 10-4 M. Moreover, it was found to be a highly sensitive aniline detection probe. At the same time, the aniline biomarker p-aminophenol in urine could also be detected, which could expand the potential applications of polymers in the fluorescence-sensing field.

18.
RSC Adv ; 14(8): 5566-5576, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38352687

RESUMO

An in situ synthesis approach is used to directly grow a microsphere of melamine-glutaraldehyde (MAGA) polymer over three-dimensional (3D) nickel foam (NF). The materials are used to produce nitrogen-doped carbon (NC) with and without NF. These precursors undergo carbonization at various temperatures, namely 400 °C, 500 °C, and 700 °C. The electrochemical properties of the materials would be significantly improved by directly growing MAGA polymer on the surface of NF. The electrochemical performance of NC/NF-400 was excellent, with a capacitance of 297 F g-1 achieved at a current density of 1 A g-1. The in situ growing approach does not necessitate the use of additional chemical agents, such as binders or conductive compounds when preparing the electrode. In addition, the material exhibits only 10% reduction in capacitance after undergoing 5000 cycles, indicating excellent cycling performance. The outstanding electrochemical performance achieved by using the in situ method of MAGA microsphere polymer on NF may be attributed to the rapid transit of ions to the electrode surfaces, facilitating effortless redox reactions.

19.
Bone Res ; 12(1): 6, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38267422

RESUMO

Skeletal stem/progenitor cell (SSPC) senescence is a major cause of decreased bone regenerative potential with aging, but the causes of SSPC senescence remain unclear. In this study, we revealed that macrophages in calluses secrete prosenescent factors, including grancalcin (GCA), during aging, which triggers SSPC senescence and impairs fracture healing. Local injection of human rGCA in young mice induced SSPC senescence and delayed fracture repair. Genetic deletion of Gca in monocytes/macrophages was sufficient to rejuvenate fracture repair in aged mice and alleviate SSPC senescence. Mechanistically, GCA binds to the plexin-B2 receptor and activates Arg2-mediated mitochondrial dysfunction, resulting in cellular senescence. Depletion of Plxnb2 in SSPCs impaired fracture healing. Administration of GCA-neutralizing antibody enhanced fracture healing in aged mice. Thus, our study revealed that senescent macrophages within calluses secrete GCA to trigger SSPC secondary senescence, and GCA neutralization represents a promising therapy for nonunion or delayed union in elderly individuals.


Assuntos
Calosidades , Fraturas Ósseas , Idoso , Humanos , Animais , Camundongos , Consolidação da Fratura , Senescência Celular , Envelhecimento , Macrófagos , Células-Tronco
20.
Neurochem Res ; 49(4): 1105-1120, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38289520

RESUMO

Reduced myelin stability observed in the early stages of Alzheimer's disease leads to spatial learning and memory impairment. Exercise has been shown to protect nerves, reduce the risk of Alzheimer's disease, and strengthen synaptic connectivity. However, the underlying mechanisms of how exercise can promote myelin repair and coordinate inflammation and proliferation are still uncertain. In this study, we conducted histological and biochemical assays of cortical lysates after behavioral testing to detect pathological changes, myelin sheath thickness, and mRNA and protein levels. It is notable that D-galactose model mice exhibited elevated miRNA-34a levels, overactive astrocytes, decreased myelin staining scores, increased apoptosis, and decreased synaptic plasticity in the brain. Significantly, after eight weeks of exercise, we observed improvements in LFB scores, NeuN( +) neuron counts, and myelin basic protein (MBP) expression. Additionally, exercise promoted the expression of oligodendrocyte markers Olig2 and PDFGR-α associated with brain proliferation, and improved spatial cognitive function. Furthermore, it decreased the inflammation caused by astrocyte secretions (TNF-α, Cox-2, CXCL2). Interestingly, we also observed downregulation of miR-34a and activation of the TAN1/PI3K/CREB signaling pathway. Our data shed light on a previously unsuspected mechanism by which exercise reduces miR-34a levels and protects neuronal function and survival by preventing excessive demyelination and inflammatory infiltration in the CNS.


Assuntos
Doença de Alzheimer , MicroRNAs , Animais , Camundongos , Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Bainha de Mielina/metabolismo , Doenças Neuroinflamatórias , Oligodendroglia/metabolismo
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