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1.
Nano Lett ; 24(21): 6344-6352, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38687224

ABSTRACT

Anisotropic two-dimensional materials present a diverse range of physical characteristics, making them well-suited for applications in photonics and optoelectronics. While mechanical properties play a crucial role in determining the reliability and efficacy of 2D material-based devices, the fracture behavior of anisotropic 2D crystals remains relatively unexplored. Toward this end, we herein present the first measurement of the anisotropic fracture toughness of 2D Ta2NiSe5 by microelectromechanical system-based tensile tests. Our findings reveal a significant in-plane anisotropic ratio (∼3.0), accounting for crystal orientation-dependent crack paths. As the thickness increases, we observe an intriguing intraplanar-to-interplanar transition of fracture along the a-axis, manifesting as stepwise crack features attributed to interlayer slippage. In contrast, ruptures along the c-axis surprisingly exhibit persistent straightness and smoothness regardless of thickness, owing to the robust interlayer shear resistance. Our work affords a promising avenue for the construction of future electronics based on nanoribbons with atomically sharp edges.

2.
Small ; 19(45): e2301959, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37329191

ABSTRACT

Strain is an effective strategy to modulate the electrical, optical, and optoelectronic properties of 2D materials. Conventional circular blisters could generate a biaxial stretching of 2D membranes with notable strain gradients along the hoop direction. However, such a deformation mode cannot be utilized to investigate mechanical responses of in-plane anisotropic 2D materials, for example, black phosphorus (BP), due to its crystallographic orientation dependence. Here, a novel rectangular-shaped bulge device is developed to uniaxially stretch the membrane, and further provide a promising platform to detect orientation-dependent mechanical and optical properties of anisotropic 2D materials. Impressively, the derived anisotropic ratio of Young's modulus of BP flakes is much higher than the values obtained via the nanoindentation method. The extra-high strain-dependent phononic anisotropy in Raman modes along different crystalline orientations is also observed. The designed rectangular budge device expands the uniaxial deformation methods available, allowing to explore the mechanical, and strain-dependent physical properties of other anisotropic 2D materials more broadly.

3.
Opt Lett ; 48(20): 5233-5236, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37831835

ABSTRACT

An all-fiber single-short-cavity dual-comb laser with a high repetition rate of up to 500 MHz and a high repetition rate difference of over 120 kHz was demonstrated. The laser setup exploits high birefringence of a polarization-maintaining gain fiber to generate asynchronous combs based on the polarization-multiplexing method. By adopting short-linear-cavity and all-birefringent configuration, a repetition rate difference several orders of magnitude larger than that of a previous work was achieved. The soliton dual-comb showed good mutual coherence and stability, which reveals the potential to enhance the acquisition rate and accuracy of dual-comb measurement systems.

4.
Mikrochim Acta ; 189(12): 477, 2022 11 26.
Article in English | MEDLINE | ID: mdl-36435879

ABSTRACT

A dual-mode immunoassay strategy based on CdS nanoparticles as signal probes with both of photoluminescent (PL) and multi-phonon resonance Raman scattering (MRRS) properties was developed. Simplified structural design and preparation were achieved due to the intrinsic integration of PL and MRRS dual signals in the single-unit CdS nanoprobes. Human immunoglobulin G (HIgG) was sensitively and specifically detected using the proposed PL-MRRS dual-mode strategy. The linear relationship between the HIgG concentration and the intensity of 707 nm PL peaks/300 cm-1 MRRS peaks under the excitation of 488 nm laser was established. The limit of detection was 0.93 fg mL-1 for PL and 1.10 fg mL-1 for MRRS. In comparison with previous IgG detection methods, the proposed method exhibited prominent advantages in detection sensitivity and working range with good stability and repeatability. An internal self-calibration was realized which ensured the accuracy and reliability of detection results. Both results of specificity experiments and serum sample analysis further confirmed the feasibility of the designed immunoassay strategy in practical serological detection.


Subject(s)
Metal Nanoparticles , Spectrum Analysis, Raman , Humans , Spectrum Analysis, Raman/methods , Phonons , Gold/chemistry , Reproducibility of Results , Immunoassay/methods , Immunoglobulin G , Metal Nanoparticles/chemistry
5.
Physiol Mol Biol Plants ; 28(2): 425-437, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35400885

ABSTRACT

Drought is the main limiting factor of maize productivity, therefore improving drought tolerance in maize has potential practical importance. Cloning and functional verification of drought-tolerant genes is of great importance to understand molecular mechanisms under drought stress. Here, we employed a bioinformatic pipeline to identify 42 ZmHDZ drought responsive genes using previously reported maize transcriptomic datasets. The coding sequences, exon-intron structure and domain organization of all the 42 genes were identified. Phylogenetic analysis revealed evolutionary conservation of members of the ZmHDZ genes in maize. Several regulatory elements associated with drought tolerance were identified in the promoter regions of ZmHDZ genes, indicating the implication of these genes in plant response to drought stress. 42 ZmHDZ genes were distributed unevenly on 10 chromosomes, and 24 pairs of gene duplications were the segmental duplication. The expression of several ZmHDZ genes was upregulated under drought stress, and ZmHDZ9 overexpressing transgenic plants exhibited higher SOD and POD activities and higher accumulation of soluble proteins under drought stress which resulted in enhanced developed phenotype and improved resistance. The present study provides evidence for the evolutionary conservation of HD-ZIP transcription factors homologs in maize. The results further provide a comprehensive insight into the roles of ZmHDZ genes in regulating drought stress tolerance in maize.

6.
Mol Genet Genomics ; 296(6): 1203-1219, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34601650

ABSTRACT

Drought severely affects the growth and development of maize, but there is a certain degree of compensation effect after rewatering. This study intends to elaborate the response mechanism of maize at the physiological and molecular level as well as excavating potential genes with strong drought resistance and recovery ability. Physiological indexes analysis demonstrated that stomata conductance, transpiration rate, photosynthesis rate, antioxidant enzymes, and proline levels in maize were significantly altered in response to drought for 60 and 96 h and rewatering for 3 days. At 60 h, 96 h, and R3d, we detected 3095, 1941, and 5966 differentially expressed genes (DEGs) and 221, 226, and 215 differentially expressed miRNAs. Weighted correlation network analysis (WGCNA) showed that DEGs responded to maize drought and rewatering through participating in photosynthesis, proline metabolism, ABA signaling, and oxidative stress. Joint analysis of DEGs, miRNA, and target genes showed that zma-miR529, miR5072, zma-miR167e, zma-miR167f, zma-miR167j, miR397, and miR6214 were involved to regulate SBPs, MYBs, ARFs, laccases, and antioxidant enzymes, respectively. Hundreds of differentially expressed DNA methylation-related 24-nt siRNA clusters overlap with DEGs, indicating that DNA methylation is involved in responses under drought stress. These results provide new insights into the molecular mechanisms of drought tolerance, and may identify new targets for breeding drought-tolerant maize lines.


Subject(s)
Adaptation, Physiological/physiology , Droughts , Gene Expression Regulation, Plant/genetics , Stress, Physiological/genetics , Zea mays/metabolism , Antioxidants/metabolism , DNA Methylation/genetics , Gene Expression Profiling , MicroRNAs/genetics , Photosynthesis , Plant Breeding , Plant Leaves/physiology , Transcriptome/genetics , Zea mays/genetics
7.
Opt Express ; 29(17): 26418-26432, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34615077

ABSTRACT

We propose a novel scheme of high doped core and stairway-index trench structure to design a manufacturable graded-index 13-core 5-LP mode fiber with low inter-core crosstalk (ICXT) and large mode differential group delay (MDGD). By using the couple power theory and the finite element method (FEM), the change ICXT of with fiber parameters are investigated. The design of core graded profile and trench structure are optimized to achieve better performance and to meet the fabrication conditions. The numerical result demonstrate that this fiber achieves a low ICXT of lower than -30dB/km (Rb≤500 mm). The bending loss values satisfy the ITU-T recommendation G.655 in 195 µm cladding diameter. Furthermore, the dispersion and the MDGD dependences on wavelength are calculated. The relative core multiplicity factor (RCMF) is obtained as 75.17, which realizes the high density multiplexing. The fabrication methods of this fiber are briefly introduced. The designed fiber may be used for Space-division multiplexing (SDM) system to solve the problem of fiber capacity limitation.

8.
Physiol Mol Biol Plants ; 27(6): 1295-1309, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34177148

ABSTRACT

MYB transcription factors play pivotal roles in hormone conduction signaling and abiotic stress response. In this study, 54 differentially expressed ZmMYB genes were identified and comprehensive analyses were conducted including gene's structure, chromosomal localization, phylogenetic tree, motif prediction, cis-elements and expression patterns. The results showed that 54 genes were unevenly distributed on 10 chromosomes and classified into eleven main subgroups by phylogenetic analysis, supported by motif and exon/intron analyses. The mainly stress-related cis-elements were ABRE, ARE, MBS and DRE-core. In addition, 8 core ZmMYB genes were identified by co-expression network. qRT-PCR results showed that the 8 ZmMYB genes exhibited different expression levels under different abiotic stresses, indicating that they were responsive to various abiotic stress. These results will provide insight for further functional investigation of ZmMYB genes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01013-2.

9.
Pak J Med Sci ; 37(5): 1408-1413, 2021.
Article in English | MEDLINE | ID: mdl-34475921

ABSTRACT

OBJECTIVE: To explore the effect of oxycodone hydrochloride combined with dexmedetomidine on the recovery quality and stress response during anesthesia in patients undergoing laparoscopic cholecystectomy (LC). METHODS: Ninety patients who had LC in Cangzhou Hospital of Integrated TCM-WM of Hebei from December 2016 to December 2019 were selected and divided into dexmedetomidine group (DEX group), oxycodone hydrochloride group (Q group), dexmedetomidine + oxycodone hydrochloride group (DQ group) by a random number table method, with 30 cases in each group. At the time before anesthesia induction (T0), and immediately (T1), 1 min (T2), 10 min (T3) and 30 minutes (T4) after extubation, the general vital signs of three groups were observed, and plasma cortisol (COR), epinephrine (E), norepinephrine (NE) and blood glucose (GLU) were measured. The spontaneous respiration recovery time, wake-up time, VAS score of each time period after extubation, extubation quality score, and adverse event rate were recorded. RESULTS: The vital signs at each time point of extubation, recovery time of spontaneous respiration, wake-up time, and extubation quality of DQ group were better than those of DEX group and Q group (P<0.05). The incidence of agitation, VAS score at T2 and T3, plasma concentrations of Cor, E, NE and Glu at T1, T3 and T4 in DQ group were significantly lower than those in Q group and DEX group (P<0.05). CONCLUSION: Oxycodone hydrochloride combined with dexmedetomidine can improve the recovery quality and reduce stress response in patients with LC after anesthesia, and can be safely used in patients with LC.

10.
Nano Lett ; 19(7): 4478-4489, 2019 07 10.
Article in English | MEDLINE | ID: mdl-31244230

ABSTRACT

Silver nanoparticles (Ag NPs) have promising plasmonic properties, however, they are rarely used in biomedical applications because of their potent toxicity. Herein, an electron compensation effect from Au to Ag was applied to design safe Au@Ag core-shell NPs. The Ag shell thickness was precisely regulated to enable the most efficient electron enrichment in Ag shell of Au@Ag2.4 NPs, preventing Ag oxidation and subsequent Ag+ ion release. X-ray photoelectron spectroscopy and X-ray absorption near-edge structure analysis revealed the electron transfer process from Au core to Ag shell, and inductively coupled plasma optical emission spectroscopy analysis confirmed the low Ag+ ion release from Au@Ag2.4 NPs. Bare Au@Ag2.4 NPs showed much lower toxicological responses than Ag NPs in BEAS-2B and Raw 264.7 cells and acute lung inflammation mouse models, and PEGylation of Au@Ag2.4 NPs could further improve their safety to L02 and HEK293T cells as well as mice through intravenous injection. Further, diethylthiatri carbocyanine iodide attached pAu@Ag2.4 NPs exhibited intense surface-enhanced Raman scattering signals and were used for Raman imaging of MCF7 cells and Raman biosensing in MCF7 tumor-bearing mice. This electron compensation effect opens up new opportunity for broadening biomedical application of Ag-based NPs.

11.
Int J Mol Sci ; 21(1)2020 Jan 05.
Article in English | MEDLINE | ID: mdl-31948071

ABSTRACT

OSCAs are hyperosmolality-gated calcium-permeable channel proteins. In this study, two co-expression modules, which are strongly associated with maize proline content, were screened by weighted correlation network analysis, including three ZmOSCA family members. Phylogenetic and protein domain analyses revealed that 12 ZmOSCA members were classified into four classes, which all contained DUF221 domain. The promoter region contained multiple core elements responsive to abiotic stresses and hormones. Colinear analysis revealed that ZmOSCAs had diversified prior to maize divergence. Most ZmOSCAs responded positively to ABA, PEG, and NaCl treatments. ZmOSCA2.3 and ZmOSCA2.4 were up-regulated by more than 200-fold under the three stresses, and showed significant positive correlations with proline content. Yeast two-hybrid and bimolecular fluorescence complementation indicated that ZmOSCA2.3 and ZmOSCA2.4 proteins interacted with ZmEREB198. Over-expression of ZmOSCA2.4 in Arabidopsis remarkably improved drought resistance. Moreover, over-expression of ZmOSCA2.4 enhanced the expression of drought tolerance-associated genes and reduced the expression of senescence-associated genes. We also found that perhaps ZmOSCA2.4 was regulated by miR5054.The results provide a high-quality molecular resource for selecting resistant breeding, and lay a foundation for elucidating regulatory mechanism of ZmOSCA under abiotic stresses.


Subject(s)
Arabidopsis/metabolism , Calcium Channels/metabolism , Cellular Senescence/genetics , Gene Expression Regulation, Plant/genetics , Stress, Physiological/genetics , Zea mays/genetics , Zea mays/metabolism , Arabidopsis/genetics , Calcium Channels/genetics , Cellular Senescence/drug effects , Droughts , Gene Expression Regulation, Plant/drug effects , MicroRNAs/metabolism , Osmotic Pressure , Phylogeny , Plants, Genetically Modified/genetics , Proline/metabolism , Promoter Regions, Genetic , Protein Domains , Salt Tolerance/genetics , Sodium Chloride/metabolism , Stress, Physiological/drug effects , Transcriptome/drug effects , Transcriptome/genetics
12.
Physiol Mol Biol Plants ; 26(4): 705-717, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32255934

ABSTRACT

The plant-specific NAC transcription factor (TFs) plays crucial role in plant growth as well as in stress resistance. In the present study, 87 Zea mays NAC TFs were obtained from the transcriptome analysis using drought-resistant maize inbred line Y882 as experimental material under PEG stress and rewatering treatment. Comprehensive analyses were conducted including genes structure, chromosomal localization, phylogenetic tree and motif prediction, cis-elements and expression patterns. The results showed that the 87 ZmNAC genes distributed on 10 chromosomes and were categorized into 15 groups based on their conserved gene structure and motifs. Phylogenetic tree analysis was also constructed referencing to the counterparts of Arabidopsis and rice, and the stress-related cis-elements in the promoter region were also analyzed. 87 ZmNAC genes exhibited different expression levels at 3 treatment points, indicating different response to drought stress. This genome-wide analysis of 87 ZmNAC genes will provide basis for further gene function detection.

13.
Phys Rev Lett ; 123(11): 116101, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31573244

ABSTRACT

Out-of-plane deformation patterns, such as buckling, wrinkling, scrolling, and folding, formed by multilayer van der Waals materials have recently seen a surge of interest. One crucial parameter governing these deformations is bending rigidity, on which significant controversy still exists despite extensive research for more than a decade. Here, we report direct measurements of bending rigidity of multilayer graphene, molybdenum disulfide (MoS_{2}), and hexagonal boron nitride (hBN) based on pressurized bubbles. By controlling the sample thickness and bubbling deflection, we observe platelike responses of the multilayers and extract both their Young's modulus and bending rigidity following a nonlinear plate theory. The measured Young's moduli show good agreement with those reported in the literature (E_{graphene}>E_{hBN}>E_{MoS_{2}}), but the bending rigidity follows an opposite trend, D_{graphene}

14.
Int J Mol Sci ; 20(17)2019 Aug 22.
Article in English | MEDLINE | ID: mdl-31443483

ABSTRACT

The basic leucine zipper (bZIP) family of transcription factors (TFs) regulate diverse phenomena during plant growth and development and are involved in stress responses and hormone signaling. However, only a few bZIPs have been functionally characterized. In this paper, 54 maize bZIP genes were screened from previously published drought and rewatering transcriptomes. These genes were divided into nine groups in a phylogenetic analysis, supported by motif and intron/exon analyses. The 54 genes were unevenly distributed on 10 chromosomes and contained 18 segmental duplications, suggesting that segmental duplication events have contributed to the expansion of the maize bZIP family. Spatio-temporal expression analyses showed that bZIP genes are widely expressed during maize development. We identified 10 core ZmbZIPs involved in protein transport, transcriptional regulation, and cellular metabolism by principal component analysis, gene co-expression network analysis, and Gene Ontology enrichment analysis. In addition, 15 potential stress-responsive ZmbZIPs were identified by expression analyses. Localization analyses showed that ZmbZIP17, -33, -42, and -45 are nuclear proteins. These results provide the basis for future functional genomic studies on bZIP TFs in maize and identify candidate genes with potential applications in breeding/genetic engineering for increased stress resistance. These data represent a high-quality molecular resource for selecting resistant breeding materials.


Subject(s)
Droughts , Gene Expression Regulation, Plant , Genes, Plant , Leucine Zippers/genetics , Stress, Physiological/genetics , Zea mays/physiology , Amino Acid Sequence , Chromosome Mapping , Computational Biology/methods , Conserved Sequence , Evolution, Molecular , Gene Duplication , Gene Expression Profiling , Genome, Plant , Genomics/methods , Multigene Family , Promoter Regions, Genetic , Transcriptome , Zea mays/classification
15.
Phys Rev Lett ; 121(26): 266101, 2018 Dec 28.
Article in English | MEDLINE | ID: mdl-30636129

ABSTRACT

Nanoblisters such as nanobubbles and nanotents formed by two-dimensional (2D) materials have been extensively exploited for strain engineering purposes as they can produce self-sustained, nonuniform in-plane strains through out-of-plane deformation. However, deterministic measure and control of strain fields in these systems are challenging because of the atomic thinness and unconventional interface behaviors of 2D materials. Here, we experimentally characterize a simple and unified power law for the profiles of a variety of nanobubbles and nanotents formed by 2D materials such as graphene and MoS_{2} layers. Using membrane theory, we analytically unveil what sets the in-plane strains of these blisters regarding their shape and interface characteristics. Our analytical solutions are validated by Raman spectroscopy measured strain distributions in bulged graphene bubbles supported by strong and weak shear interfaces. We advocate that both the strain magnitudes and distributions can be tuned by 2D material-substrate interface adhesion and friction properties.

16.
Phys Rev Lett ; 119(3): 036101, 2017 Jul 21.
Article in English | MEDLINE | ID: mdl-28777616

ABSTRACT

Monolayer two-dimensional (2D) crystals exhibit a host of intriguing properties, but the most exciting applications may come from stacking them into multilayer structures. Interlayer and interfacial shear interactions could play a crucial role in the performance and reliability of these applications, but little is known about the key parameters controlling shear deformation across the layers and interfaces between 2D materials. Herein, we report the first measurement of the interlayer shear stress of bilayer graphene based on pressurized microscale bubble loading devices. We demonstrate continuous growth of an interlayer shear zone outside the bubble edge and extract an interlayer shear stress of 40 kPa based on a membrane analysis for bilayer graphene bubbles. Meanwhile, a much higher interfacial shear stress of 1.64 MPa was determined for monolayer graphene on a silicon oxide substrate. Our results not only provide insights into the interfacial shear responses of the thinnest structures possible, but also establish an experimental method for characterizing the fundamental interlayer shear properties of the emerging 2D materials for potential applications in multilayer systems.

17.
Talanta ; 278: 126495, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38955105

ABSTRACT

Accurate and sensitive determination of human immunoglobulin G (HIgG) level is critical for diagnosis and treatment of various diseases, including rheumatoid arthritis, humoral immunodeficiencies, and infectious disease. In this study, versatile tri-signal probes were developed by preparing CdS@SiO2 nanorods that integrate photoluminescence (PL), multi-phonon resonant Raman scattering (MRRS) and infrared absorption (IRA) properties. Through the coating of multiple CdS nanoparticles as cores within SiO2 shells, the PL and MRRS properties of CdS were improved, resulting in a significantly lowered limit of detection (LOD), with the lowest LOD of 12.37 ag mL-1. Integration with the distinctive IRA property of SiO2 shells widened the detection range towards higher concentrations, establishing a final linear range of 50 ag mL-1 to 10 µg mL-1. The remarkable consistency among the three signals highlighted the robust internal verification capability for accurate detection. This approach enhances flexibility in selecting detection methodologies to suit diverse scenarios, facilitating HIgG detection. The tri-signal nanoprobes also exhibited excellent detection selectivity, specificity and repeatability. This study presents a fresh idea for developing high-performance detection strategies.

18.
Nat Commun ; 15(1): 865, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38286850

ABSTRACT

Spintronic device is the fundamental platform for spin-related academic and practical studies. However, conventional techniques with energetic deposition or boorish transfer of ferromagnetic metal inevitably introduce uncontrollable damage and undesired contamination in various spin-transport-channel materials, leading to partially attenuated and widely distributed spintronic device performances. These issues will eventually confuse the conclusions of academic studies and limit the practical applications of spintronics. Here we propose a polymer-assistant strain-restricted transfer technique that allows perfectly transferring the pre-patterned ferromagnetic electrodes onto channel materials without any damage and change on the properties of magnetism, interface, and channel. This technique is found productive for pursuing superior-quality spintronic devices with high controllability and reproducibility. It can also apply to various-kind (organic, inorganic, organic-inorganic hybrid, or carbon-based) and diverse-morphology (smooth, rough, even discontinuous) channel materials. This technique can be very useful for reliable device construction and will facilitate the technological transition of spintronic study.

19.
Article in English | MEDLINE | ID: mdl-36674011

ABSTRACT

Organizational career management (OCM) is believed to be a useful practice to stimulate the potential of employees. However, how this can be achieved is still under investigation. This research aims to explore the mechanisms that explain the effects of OCM by clarifying its impact on employees' psychological states and their capability, based on a socially embedded model of thriving. To examine our hypotheses, we conducted a three-wave survey study with 272 full-time employees in China from diverse industries. The study lasted for three months and there was a one-month interval after each wave. We asked the participants to report OCM, career plateau and demographic variables at Time 1, their appraisal of learning and vitality at Time 2, and their self-perceived employability and job burnout at Time 3. We utilized regression analysis to examine our theoretical model and path analysis using the bias-corrected bootstrap method to test the significance of the indirect and moderation effects. The findings showed that OCM positively affected employees' learning and vitality at work, which increased their self-perceived employability and subsequently decreased job burnout. Furthermore, the effects of OCM were found to be weaker for employees with a high degree of career plateau. These findings demonstrate that OCM benefits employees by "enabling" and "energizing" them to better themselves in terms of their employment and they shed light on the boundary condition of the career plateau. Therefore, organizations may provide OCM to facilitate employees' capability and their motivation to engage in self-development, and to further enhance the effects by decreasing their perception of a career plateau.


Subject(s)
Burnout, Professional , Employment , Humans , Employment/psychology , Occupations , Burnout, Professional/psychology , China
20.
Front Cell Dev Biol ; 11: 1227440, 2023.
Article in English | MEDLINE | ID: mdl-37766965

ABSTRACT

Background: MicroRNA-216a-5p (miR-216a-5p) mediates inflammatory responses and neuronal injury to participate in the pathology of spinal cord injury (SCI). This study intended to explore the engagement of bone marrow mesenchymal stem cell exosomes (BMSC-Exo)-derived miR-216a-5p in locomotor performance, neuronal injury, and microglia-mediated inflammation in SCI rats. Methods: Rat BMSC or BMSC-Exo was injected into SCI rats. GW4869 treatment was adopted to suppress the exosome secretion from BMSC. Subsequently, miR-216a-5p-overexpressed BMSC-Exo (BMSC-miR-Exo) or negative-control-overexpressed BMSC-Exo (BMSC-NC-Exo) were injected into SCI rats. Results: The injection of BMSC or BMSC-Exo enhanced locomotor performance reflected by Basso, Beattie & Bresnahan score (p < 0.001), and neuronal viability reflected by NeuN+ cells (p < 0.01), but attenuated neuronal apoptosis reflected by TUNEL positive rate, cleaved-caspase-3 expression, and B-cell leukemia/lymphoma-2 expression (p < 0.05). Additionally, the injection of BMSC or BMSC-Exo suppressed microglia M1 polarization-mediated inflammation reflected by IBA1+iNOS+ cells, tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 (p < 0.01). Notably, the effect of BMSC on the above functions was retarded by the GW4869 treatment (most p < 0.05). Subsequently, the injection of BMSC-miR-Exo further improved locomotor performance (p < 0.05), while inhibiting neuronal apoptosis (p < 0.05) and microglia M1 polarization-mediated inflammation (p < 0.05) compared to BMSC-NC-Exo. Interestingly, the injection of BMSC-miR-Exo reduced toll-like receptor 4 (TLR4) (p < 0.01), myeloid differentiation factor 88 (p < 0.05), and nuclear factor kappa B (NF-κB) (p < 0.05) expressions versus BMSC-NC-Exo. Conclusion: BMSC-Exo-derived miR-216a-5p enhances functional recovery by attenuating neuronal injury and microglia-mediated inflammation in SCI, which may be attributable to its inhibition of the TLR4/NF-κB pathway.

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