Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 614
Filtrer
1.
Neural Regen Res ; 20(1): 277-290, 2025 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-38767492

RÉSUMÉ

JOURNAL/nrgr/04.03/01300535-202501000-00035/figure1/v/2024-05-14T021156Z/r/image-tiff Our previous study found that rat bone marrow-derived neural crest cells (acting as Schwann cell progenitors) have the potential to promote long-distance nerve repair. Cell-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular communication. Nevertheless, the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain unclear. To investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves, we collected conditioned culture medium from hypoxia-pretreated neural crest cells, and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose deprivation. The mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest cells. We performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest cells. Subsequently, to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons, we used a microfluidic axonal dissociation model of sensory neurons in vitro, and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons, which was greatly dependent on loaded miR-21-5p. Finally, we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb, as well as muscle tissue morphology of the hind limbs, were obviously restored. These findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in miRNA-21-5p. miRNA-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell secretome. This helps to explain the mechanism of action of the secretome and extracellular vesicles of neural crest cells in repairing damaged peripheral nerves, and also promotes the application of miR-21-5p in tissue engineering regeneration medicine.

2.
J Phys Chem C Nanomater Interfaces ; 128(38): 16265-16273, 2024 Sep 26.
Article de Anglais | MEDLINE | ID: mdl-39355009

RÉSUMÉ

Low-dimensional van der Waals (vdW) three-dimensional (3D) topological insulators (TIs) have been overlooked, regarding their electromechanical properties. In this study, we experimentally investigate the electromechanical coupling of low-dimensional 3D TIs with a centrosymmetric crystal structure, where a binary compound, bismuth selenide (Bi2Se3), is taken as an example. Piezoresponse force microscopy (PFM) results of Bi2Se3 nanoflakes show that the material exhibits both out-of-plane and in-plane electromechanical responses. With careful analyses, the electromechanical responses are verified to arise from the converse flexoelectricity. The Bi2Se3 nanoflakes have a decreasing effective out-of-plane piezoelectric coefficient d 33 eff with the thickness increasing, with the d 33 eff value of ∼0.65 pm V-1 for the 37 nm-thick sample. The measured effective out-of-plane piezoelectric coefficient is mainly contributed by the flexoelectric coefficient, µ39, which is estimated to be approximately 0.13 nC m-1. The results can help to understand the flexoelectricity of low-dimensional vdW TIs with centrosymmetric crystal structures, which is crucial for the design of nanoelectromechanical devices and spintronics built by vdW TIs.

3.
Nano Lett ; 2024 Sep 19.
Article de Anglais | MEDLINE | ID: mdl-39297742

RÉSUMÉ

Solid-state quantum emitters (QEs) with arbitrary direction emission and well-defined polarization are critical for scalable single-photon sources and quantum information processing. However, the design strategy for on-chip generation of off-normal photon emission with high-purity polarization characteristics has so far remained elusive. Here, we introduce the anisotropic holography metasurfaces for efficiently manipulating the emission direction and polarization of QE. The proposed method offers a flexible way to realize phase matching in surface plasmon scattering with spatially varying filling factors and provides an efficient route for designing advanced QE-coupled metasurfaces. By nonradiatively coupling nanodiamonds with metasurfaces, we experimentally demonstrate on-chip generation of well-collimated single-photon emission propagating along off-normal directions (i.e., 20° and 30°) featuring a divergence angle lower than 2.5°. The experimental average degree of linear polarization attains up to >0.98, thereby revealing markedly high polarization purity. This study facilitates applications of QEs in the deployment of integrated quantum networks.

4.
BMC Pulm Med ; 24(1): 473, 2024 Sep 27.
Article de Anglais | MEDLINE | ID: mdl-39334033

RÉSUMÉ

BACKGROUND: The expression of 2'-5'-oligoadenylate synthetase 1 (OAS1) in lung cancer has been validated in numerous studies. However, the prognostic value of OAS1 expression in lung adenocarcinoma (LUAD) still remains unclear. This study aimed to reveal the prognostic value and associated molecular mechanisms of OAS1 expression in LUAD. METHODS: Gene expression data of LUAD were extracted from online databases. Gene and protein expression levels of OAS1 in LUAD and normal samples were revealed, followed by prognostic analysis of OAS1. Next, we conducted a thorough bioinformatics analysis to examine the enrichment of key functional and biological signaling pathways and their correlation with the abundance of immune cells. The independent prognoses, drug responses, and PPI networks associated with OAS1 were analyzed. OAS1 expression was evaluated in LUAD tissues and cell lines. OAS1 was knocked down by siRNA transfection, followed by CCK8, colony formation, and wound-healing assays. RESULTS: Gene and protein expression levels of OAS1 in LUAD samples were significantly higher than those in normal samples (all P < 0.05). OAS1 stimulation were correlated with poor prognosis, lymph node metastasis, advanced tumor stage, immune cells, and immunomodulators. The prognostic value of OAS1 in LUAD was determined via univariate regression analysis. In total, 10 OAS1-associated genes were revealed via PPI analysis of OAS1, which were primarily enriched in functions, such as the negative regulation of viral genome replication. Transcriptional analysis revealed several OAS1-related interactions, including STAT3-miR-21-OAS1. STAT3 was overexpressed and miR-21 was expressed in LUAD cells. Upregulation of OAS1 protein was determined in LUAD tissues and cell lines. OAS1 knockdown significantly reduced proliferation and migration of LUAD cells. CONCLUSIONS: OAS1 overexpression influenced survival and immune cell infiltration in patients with LUAD, which might be a potential prognostic gene for LUAD. Moreover, OAS1 contributed to LUAD progression by participating in STAT3-miR-21-OAS1 axis.


Sujet(s)
2',5'-Oligoadenylate synthetase , Adénocarcinome pulmonaire , Tumeurs du poumon , Humains , 2',5'-Oligoadenylate synthetase/génétique , 2',5'-Oligoadenylate synthetase/métabolisme , Pronostic , Adénocarcinome pulmonaire/génétique , Adénocarcinome pulmonaire/anatomopathologie , Adénocarcinome pulmonaire/métabolisme , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/génétique , Tumeurs du poumon/métabolisme , Lignée cellulaire tumorale , Régulation de l'expression des gènes tumoraux , Femelle , Mâle , Prolifération cellulaire/génétique , Marqueurs biologiques tumoraux/métabolisme , Marqueurs biologiques tumoraux/génétique , Biologie informatique , Facteur de transcription STAT-3/métabolisme , Facteur de transcription STAT-3/génétique , Adulte d'âge moyen
5.
Light Sci Appl ; 13(1): 267, 2024 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-39313505

RÉSUMÉ

Developing a bright, deterministic source of entangled photon pairs has been an outstanding scientific and technological challenge. Semiconductor quantum dots are a promising candidate for this task. A new device combining a circular Bragg resonator and a piezoelectric actuator achieves high brightness and entanglement fidelity simultaneously, overcoming previous limitations. This breakthrough enhances quantum dot applications in entanglement-based quantum communication protocols.

6.
Int J Biol Macromol ; 279(Pt 4): 135376, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39244119

RÉSUMÉ

Adipocyte-secreted factors intricately regulate adipose tissue function, and the underlying molecular mechanisms are only partially understood. However, the function of PRELP, which is a key component of the extracellular matrix (ECM) in adipocytes, remains largely unknown. In this study, we demonstrate that PRELP was upregulated in both obese humans and mice, which exhibited a positive correlation with metabolic disorders. PRELP knockout could resist HFD-induced obesity and inhibit adipocyte differentiation. PRELP knockout improved glucose tolerance, insulin sensitivity and alleviated adipose tissue fibrosis. Mechanistically, PRELP was secreted into the ECM and bound to the extracellular domain of its receptor p75NTR in adipocytes, which further activated the FAK/MAPK (JNK, p38 MAPK, ERK1/2) signaling pathway, promoting adipocyte differentiation and exacerbating adipocyte fibrosis. Adipocyte PRELP plays a pivotal role in regulating obesity and adipose tissue fibrosis through an autocrine manner, and PRELP may be a therapeutic target for obesity and its related metabolic disorders.


Sujet(s)
Adipocytes , Tissu adipeux , Fibrose , Système de signalisation des MAP kinases , Animaux , Souris , Humains , Tissu adipeux/métabolisme , Adipocytes/métabolisme , Différenciation cellulaire , Obésité/métabolisme , Obésité/anatomopathologie , Récepteurs facteur croissance nerf/métabolisme , Récepteurs facteur croissance nerf/génétique , Mâle , Souris knockout , Focal adhesion kinase 1/métabolisme , Focal adhesion kinase 1/génétique , Liaison aux protéines , Adipogenèse , Souris de lignée C57BL , Protéines de tissu nerveux
7.
Pediatr Infect Dis J ; 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-39348496

RÉSUMÉ

Intraspinal cold abscesses caused by macrolide-resistant Mycoplasma pneumoniae in patients with X-linked agammaglobulinemia have not yet been described to our knowledge. Here we describe a patient with X-linked agammaglobulinemia who developed an intraspinal cold abscess caused by macrolide-resistant M. pneumoniae . Genetic analysis revealed a hemizygous c.1566 + 1G > C (IVS15 + 1G > C) mutation in BTK gene. The patient showed relatively naive T cells and a significant proliferative defect.

8.
Clin Lab ; 70(8)2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39193963

RÉSUMÉ

BACKGROUND: A new chemiluminescence assay, the Anti-TP-Ⅱ assay, is going to be commercially available in clinical laboratories in China and other countries. This study examined the performance of the new assay for the detection of TP infection and compared it with that of the Anti-TP assay by using large amounts of clinical samples. METHODS: The precision, accuracy, anti-interference ability, and the clinical sensitivity and specificity of the Anti-TP-Ⅱ assay were evaluated. In addition, compared with those of the Anti-TP assay, the false positive and false negative rates of the Anti-TP-Ⅱ assay were evaluated for 2,436 clinical routine samples and 711 preselected Anti-TP assay reactive samples. Discrepancy of the samples was investigated with the recomLinec Treponema IgM/IgG kit or the Elecsys syphilis assay. RESULTS: The precision, accuracy, and anti-interference ability of the Anti-TP-Ⅱ assay met the national standard of China, and there was an overall agreement of 96.75% (Kappa = 0.91) between the two assays. The sensitivity and specificity of the Anti-TP-Ⅱ assay were 100% (95% CI: 94.13% to 100%) and 99.92% (95% CI: 99.70% to 99.99%), respectively. Compared with the Anti-TP assay, the Anti-TP-Ⅱ assay significantly reduced the number of borderline samples and the false positive rate. CONCLUSIONS: Considering its excellent performance, the Anti-TP-Ⅱ assay is a good screening test for high-throughput laboratories and can replace the previous generation of reagents, the Anti-TP assay, with a superior specificity.


Sujet(s)
Anticorps antibactériens , Mesures de luminescence , Sensibilité et spécificité , Syphilis , Treponema pallidum , Humains , Mesures de luminescence/méthodes , Treponema pallidum/immunologie , Syphilis/diagnostic , Syphilis/microbiologie , Syphilis/immunologie , Syphilis/sang , Anticorps antibactériens/sang , Anticorps antibactériens/immunologie , Reproductibilité des résultats , Sérodiagnostic de la syphilis/méthodes , Chine , Faux positifs , Mâle , Femelle , Faux négatifs
9.
Fish Shellfish Immunol ; 153: 109852, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39173982

RÉSUMÉ

Cottonseed meal (CSM) and cottonseed protein concentrate (CPC) serve as protein alternatives to fish meal and soybean meal in the feed industry. However, the presence of gossypol residue in CSM and CPC can potentially trigger severe intestinal inflammation, thereby restricting the widespread utilization of these two protein sources. Probiotics are widely used to prevent or alleviate intestinal inflammation, but their efficacy in protecting fish against gossypol-induced enteritis remains uncertain. Here, the protective effect of Pediococcus pentosaceus, a strain isolated from the gut of Nile tilapia (Oreochromis niloticus), was evaluated. Three diets, control diet (CON), gossypol diet (GOS) and GOS supplemented with P. pentosaceus YC diet (GP), were used to feed Nile tilapia for 10 weeks. After the feeding trial, P. pentosaceus YC reduced the activity of myeloperoxidase (MPO) in the proximal intestine (PI) and distal intestine (DI). Following a 7-day exposure to Aeromonas hydrophila, the addition of P. pentosaceus YC was found to increase the survival rate of the fish. P. pentosaceus YC significantly inhibited the oxidative stress caused by gossypol, which was evidenced by lower reactive oxygen species (ROS) and malondialdehyde (MDA), as well as higher activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in PI and DI. Addition of P. pentosaceus YC significantly inhibited enteritis, with the lower expression of pro-inflammatory cytokines (il-1ß, il-6, il-8) and higher expression of anti-inflammatory cytokines tgf-ß. RNA-seq analysis indicated that P. pentosaceus YC supplementation significantly inhibited nlrc3 and promoted nf-κb expression in PI and DI, and the siRNA interference experiment in vivo demonstrated that intestinal inflammation was mediated by NLRC3/NF-κB/IL-1ß signaling pathway. Fecal bacteria transplantation experiment demonstrated that gut microbiota mediated the protective effect of P. pentosaceus YC. These findings offer valuable insights into the application of P. pentosaceus YC for alleviating gossypol-induced intestinal inflammation in fish.


Sujet(s)
Aliment pour animaux , Cichlides , Maladies des poissons , Gossypol , Pediococcus pentosaceus , Probiotiques , Transduction du signal , Animaux , Cichlides/immunologie , Maladies des poissons/immunologie , Maladies des poissons/induit chimiquement , Maladies des poissons/prévention et contrôle , Probiotiques/pharmacologie , Probiotiques/administration et posologie , Aliment pour animaux/analyse , Transduction du signal/effets des médicaments et des substances chimiques , Gossypol/administration et posologie , Gossypol/pharmacologie , Régime alimentaire/médecine vétérinaire , Interleukine-1 bêta/génétique , Interleukine-1 bêta/métabolisme , Aeromonas hydrophila/physiologie , Facteur de transcription NF-kappa B/métabolisme , Facteur de transcription NF-kappa B/génétique , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Intestins/effets des médicaments et des substances chimiques , Intestins/immunologie , Inflammation/médecine vétérinaire , Inflammation/induit chimiquement , Inflammation/immunologie , Infections bactériennes à Gram négatif/médecine vétérinaire , Infections bactériennes à Gram négatif/immunologie , Protéines de poisson/génétique , Protéines de poisson/métabolisme , Protéines de poisson/immunologie , Entérite/médecine vétérinaire , Entérite/prévention et contrôle , Entérite/induit chimiquement , Entérite/immunologie , Entérite/microbiologie
10.
Int J Biochem Cell Biol ; 175: 106638, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39173825

RÉSUMÉ

Obesity is one of the threats to human health and survival. High fat diet (HFD)-induced obesity leads to adipose tissue fibrosis and a series of metabolic diseases. There are some people still thin under HFD, a phenomenon known as the "obesity resistance (OR) phenotype". It was found that Iroquois homeobox 3 (IRX3) is considered as a regulator in obesity, but the regulatory mechanism between OR and IRX3 is still unclear. In this study, we investigated OR on a HFD and the role of the IRX3 gene. Using mice, we observed that OR mice had lower body weights, reduced liver lipid synthesis, and increased white adipose tissue (WAT) lipolysis compared to obesity-prone (OP) mice. Additionally, OR mice exhibited spontaneous WAT browning and less fibrosis, correlating with higher Irx3 expression. Utilizing 3T3-L1 differentiated adipocytes, our study demonstrated that overexpression of Irx3 promoted thermogenesis-related gene expression and reduced adipocyte fibrosis. Therefore, Irx3 promotes WAT browning and inhibits fibrosis in OR mice. These results provide insight into the differences between obesity and OR, new perspectives on obesity treatment, and guidance for lessening adipose tissue fibrosis.


Sujet(s)
Tissu adipeux brun , Alimentation riche en graisse , Fibrose , Protéines à homéodomaine , Obésité , Facteurs de transcription , Animaux , Protéines à homéodomaine/génétique , Protéines à homéodomaine/métabolisme , Souris , Obésité/métabolisme , Obésité/génétique , Obésité/anatomopathologie , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique , Tissu adipeux brun/métabolisme , Tissu adipeux brun/anatomopathologie , Alimentation riche en graisse/effets indésirables , Mâle , Souris de lignée C57BL , Tissu adipeux blanc/métabolisme , Tissu adipeux blanc/anatomopathologie , Cellules 3T3-L1 , Thermogenèse/génétique
11.
Chembiochem ; : e202400363, 2024 Aug 21.
Article de Anglais | MEDLINE | ID: mdl-39166897

RÉSUMÉ

Mapping the endocytic vesicular acidification process is of prior importance to better understand the health and pathological processes of cells. Herein, by integrating a pH-sensitive i-motif and a pair of fluorescence resonance energy transfer (FRET) into a tetrahedral DNA framework (TDF), we develop a pH-responsive DNA nanomachine, allowing for efficient sensing of pH from 7.0 to 5.5 via the pH-triggered spatial proximity modulation of FRET. The inheriting endo-lysosome-targeting ability of TDF enables spatiotemporal tracking of endocytic vesicle acidification during the endosomal maturation process. Analysis of pH-dependent FRET response at single fluorescent spot level reveals the significant difference of endocytic vesicular acidification between normal and cancer cells. The performance of pH-responsive DNA nanomachine underlines its potential for studies on vesicle acidification-related pathologies as a universal platform.

12.
Front Public Health ; 12: 1368933, 2024.
Article de Anglais | MEDLINE | ID: mdl-39114511

RÉSUMÉ

Objective: Sarcopenia is a gradually advancing systemic disorder affecting skeletal muscles, primarily distinguished by diminished muscle mass and functional decline. As of present, a universally accepted diagnostic criterion for sarcopenia has yet to be established. From the perspective of the constitution theory in traditional Chinese medicine (TCM), the Yin-deficiency constitution is believed to have a significant correlation with the development of sarcopenia. The primary objective of this study was to examine the potential association between sarcopenia and Yin-deficiency constitution. Methods: The present study is a cross-sectional analysis. The Asian Working Group for Sarcopenia (AWGS) recommended a diagnostic criterion for sarcopenia. A total of 141 participants over 50 years of age were diagnosed with sarcopenia. To determine the constitution of each patient, classification and determination standards were used in traditional Chinese medicine. In this study, a combination of logistic regression and propensity score matching (PSM) was employed to analyze a dataset comprising 1,372 eligible observations. The diagnostic efficacy of the test in distinguishing sarcopenia was assessed through receiver operating characteristic (ROC) curve analysis. Results: The relationship between Yin-deficiency constitution and sarcopenia was examined using logistic regression analysis. In the crude model, the odds ratio (OR) was found to be 3.20 (95% confidence interval [CI]: 1.70-6.03). After adjusting for various confounding factors, including gender, sex, 6 m walking test/(m/s), SMI, and maximum grip strength/kg, the OR increased to 9.70 (95% CI: 3.20-69.38). The associations between seven other biased traditional Chinese medicine (TCM) constitutions and sarcopenia were not found to be statistically significant in the fully adjusted model. The propensity score matching (PSM) analysis yielded consistent results with the logistic regression analysis. Receiver operating characteristic (ROC) curve analysis showed that the AUC of the Yin-deficiency constitution combined with age and gender reached 0.707. Conclusion: Among the nine TCM constitutions examined, the Yin-deficiency constitution demonstrates an independent association with sarcopenia. Yin-deficiency constitution may serve as a potential risk factor for the development of sarcopenia. To establish a causal relationship, further experimental investigations are warranted. The diagnostic performance of sarcopenia is effectively demonstrated by the Yin-deficiency constitution combined with age and gender.


Sujet(s)
Médecine traditionnelle chinoise , Sarcopénie , Humains , Sarcopénie/diagnostic , Études transversales , Femelle , Mâle , Sujet âgé , Adulte d'âge moyen , Déficit du Yin/diagnostic , Courbe ROC , Sujet âgé de 80 ans ou plus
13.
Adv Sci (Weinh) ; : e2406571, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39119949

RÉSUMÉ

Janus metasurfaces, exemplifying two-faced 2D metamaterials, have shown unprecedented capabilities in asymmetrically manipulating the wavefront of electromagnetic waves in both forward and backward propagating directions, enabling novel applications in asymmetric information processing, security, and signal multiplexing. However, current Janus metasurfaces only allow for directional phase manipulation, hindering their broader application potential. Here, the study proposes a versatile Janus metasurface platform that can directionally control the phase and polarization of terahertz waves by integrating functionalities of half-wave plates, quarter-wave plates, and metallic gratings within a cascaded metasurface structure. As a proof-of-principle, the study experimentally demonstrates Janus metasurfaces capable of independent and simultaneous control over phase and polarization, showcasing propagation direction-encoded focusing and polarization conversion. Moreover, the directionally focused points are utilized with distinct polarization states for advanced applications in direction- and polarization-sensitive detection and imaging. This unique strategy for simultaneous phase and polarization control with direction-dependent versatility opens new avenues for designing ultra-compact devices with significant implications in imaging, encryption, and data storage.

14.
Nano Lett ; 24(33): 10106-10113, 2024 Aug 21.
Article de Anglais | MEDLINE | ID: mdl-39053013

RÉSUMÉ

Strain-free GaAs/AlGaAs semiconductor quantum dots (QDs) grown by droplet etching and nanohole infilling (DENI) are highly promising candidates for the on-demand generation of indistinguishable and entangled photon sources. The spectroscopic fingerprint and quantum optical properties of QDs are significantly influenced by their morphology. The effects of nanohole geometry and infilled material on the exciton binding energies and fine structure splitting are well-understood. However, a comprehensive understanding of GaAs/AlGaAs QD morphology remains elusive. To address this, we employ high-resolution scanning transmission electron microscopy (STEM) and reverse engineering through selective chemical etching and atomic force microscopy (AFM). Cross-sectional STEM of uncapped QDs reveals an inverted conical nanohole with Al-rich sidewalls and defect-free interfaces. Subsequent selective chemical etching and AFM measurements further reveal asymmetries in element distribution. This study enhances the understanding of DENI QD morphology and provides a fundamental three-dimensional structural model for simulating and optimizing their optoelectronic properties.

15.
Eur J Neurosci ; 60(4): 4503-4517, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38951719

RÉSUMÉ

Myelin sheath plays important roles in information conduction and nerve injury repair in the peripheral nerve system (PNS). Enhancing comprehension of the structure and components of the myelin sheath in the PNS during development would contribute to a more comprehensive understanding of the developmental and regenerative processes. In this research, the structure of sciatic nerve myelin sheath in C57BL/6 mice from embryonic day 14 (E14) to postnatal 12 months (12M) was observed with transmission electron microscopy. Myelin structure appeared in the sciatic nerve as early as E14, and the number and thickness of myelin lamellar gradually increased with the development until 12M. Transcriptome analysis was performed to show the expressions of myelin-associated genes and transcriptional factors involved in myelin formation. The genes encoding myelin proteins (Mag, Pmp22, Mpz, Mbp, Cnp and Prx) showed the same expression pattern, peaking at postnatal day 7 (P7) and P28 after birth, whereas the negative regulators of myelination (c-Jun, Tgfb1, Tnc, Cyr61, Ngf, Egr1, Hgf and Bcl11a) showed an opposite expression pattern. In addition, the expression of myelin-associated proteins and transcriptional factors was measured by Western blot and immunofluorescence staining. The protein expressions of MAG, PMP22, MPZ, CNPase and PRX increased from E20 to P14. The key transcriptional factor c-Jun co-localized with the Schwann cells Marker S100ß and decreased after birth, whereas Krox20/Egr2 increased during development. Our data characterized the structure and components of myelin sheath during the early developmental stages, providing insights for further understanding of PNS development.


Sujet(s)
Souris de lignée C57BL , Gaine de myéline , Nerf ischiatique , Animaux , Gaine de myéline/métabolisme , Nerf ischiatique/métabolisme , Nerf ischiatique/croissance et développement , Nerf ischiatique/ultrastructure , Souris , Protéines de la myéline/métabolisme , Protéines de la myéline/génétique
16.
Light Sci Appl ; 13(1): 150, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38956020

RÉSUMÉ

Quantum key distribution (QKD) enables the transmission of information that is secure against general attacks by eavesdroppers. The use of on-demand quantum light sources in QKD protocols is expected to help improve security and maximum tolerable loss. Semiconductor quantum dots (QDs) are a promising building block for quantum communication applications because of the deterministic emission of single photons with high brightness and low multiphoton contribution. Here we report on the first intercity QKD experiment using a bright deterministic single photon source. A BB84 protocol based on polarisation encoding is realised using the high-rate single photons in the telecommunication C-band emitted from a semiconductor QD embedded in a circular Bragg grating structure. Utilising the 79 km long link with 25.49 dB loss (equivalent to 130 km for the direct-connected optical fibre) between the German cities of Hannover and Braunschweig, a record-high secret key bits per pulse of 4.8 × 10-5 with an average quantum bit error ratio of ~ 0.65% are demonstrated. An asymptotic maximum tolerable loss of 28.11 dB is found, corresponding to a length of 144 km of standard telecommunication fibre. Deterministic semiconductor sources therefore challenge state-of-the-art QKD protocols and have the potential to excel in measurement device independent protocols and quantum repeater applications.

17.
Bioact Mater ; 40: 378-395, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-38978801

RÉSUMÉ

Extracellular vesicles from skin-derived precursor Schwann cells (SKP-SC-EVs) promote neurite outgrowth in culture and enhance peripheral nerve regeneration in rats. This study aimed at expanding the application of SKP-SC-EVs in nerve grafting by creating a chitosan/PLGA-based, SKP-SC-EVs-containing tissue engineered nerve graft (TENG) to bridge a 40-mm long sciatic nerve defect in dogs. SKP-SC-EVs contained in TENGs significantly accelerated the recovery of hind limb motor and electrophysiological functions, supported the outgrowth and myelination of regenerated axons, and alleviated the denervation-induced atrophy of target muscles in dogs. To clarify the underlying molecular mechanism, we observed that SKP-SC-EVs were rich in a variety of miRNAs linked to the axon growth of neurons, and miR-30b-5p was the most important among others. We further noted that miR-30b-5p contained within SKP-SC-EVs exerted nerve regeneration-promoting effects by targeting the Sin3a/HDAC complex and activating the phosphorylation of ERK, STAT3 or CREB. Our findings suggested that SKP-SC-EVs-incorporating TENGs represent a novel type of bioactive material with potential application for peripheral nerve repair in the clinic.

18.
Clin Transl Med ; 14(7): e1742, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38925910

RÉSUMÉ

BACKGROUND: White adipose tissue (WAT) has a key role in maintaining energy balance throughout the body, and their dysfunction take part in the regulation of diabetes mellitus. However, the internal regulatory mechanisms underlying are still unknown. METHODS AND RESULTS: We generated adipocyte-specific FAK KO (FAK-AKO) mice and investigated their phenotype. The cascade of adipocyte, macrophage in adipocyte tissues, and pancreatic ß-cells were proposed in FAK-AKO mice and validated by cell line studies using 3T3-L1, Raw264.7 and Min6. The FAK-AKO mice exhibited glucose intolerance, reduced adipose tissue mass and increased apoptosis, lipolysis and inflammatory response in adipose tissue. We further demonstrate that adipocyte FAK deletion increases ß cell apoptosis and inflammatory infiltrates into islets, which is potentiated if mice were treated with STZ. In the STZ-induced diabetes model, FAK AKO mice exhibit less serum insulin content and pancreatic ß cell area. Moreover, serum pro-inflammatory factors increased and insulin levels decreased after glucose stimulation in FAK AKO mice. In a parallel vitro experiment, knockdown or inhibition of FAK during differentiation also increased apoptosis, lipolysis and inflammatory in 3T3-L1 adipocytes, whereas the opposite was observed upon overexpression of FAK. Moreover, coculturing LPS-treated RAW264.7 macrophages with knockdown FAK of 3T3-L1 adipocytes increased macrophage pro-inflammatory response. Furthermore, conditioned medium from above stimulated Min6 cells apoptosis (with or without STZ), whereas the opposite was observed upon overexpression of FAK. Mechanistically, FAK protein interact with TRAF6 in adipocytes and knockdown or inhibition of FAK activated TRAF6/TAK1/NF-κB signaling, which exacerbates inflammation of adipocytes themselves. CONCLUSION: Adipocyte FAK deletion promotes both adipocyte apoptosis and adipose tissue inflammation. Pro-inflammatory factors released by the FAK-null adipose tissue further trigger apoptosis in pancreatic islets induced by the administration of STZ, thereby exacerbating the diabetes mellitus. This study reveals a link between FAK-mediated adipose inflammation and diabetes mellitus, a mechanism that has not been previously recognized.


Sujet(s)
Adipocytes , Apoptose , Diabète expérimental , Focal adhesion kinase 1 , Cellules à insuline , Souris knockout , Animaux , Souris , Apoptose/génétique , Cellules à insuline/métabolisme , Adipocytes/métabolisme , Focal adhesion kinase 1/métabolisme , Focal adhesion kinase 1/génétique , Diabète expérimental/métabolisme , Inflammation/métabolisme , Inflammation/génétique , Mâle , Tissu adipeux/métabolisme , Modèles animaux de maladie humaine
19.
J Am Chem Soc ; 146(31): 21348-21356, 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-38905206

RÉSUMÉ

Quantum dots (QDs) exhibit superior brightness and photochemical stability, making them the preferred option for highly sensitive single-molecule detection compared with fluorescent dyes or proteins. Nevertheless, their high surface energy leads to nonspecific adsorption and poor colloidal stability. In the past decades, we have found that QD-based fluorescent nanoparticles (FNs) can not only address these limitations but also enhance detection sensitivity. However, the photoluminescence quantum yield (PLQY) of FNs is significantly lower compared with that of original QDs. It is urgent to develop a strategy to solve the issue, aiming to further enhance detection sensitivity. In this study, we found that the decrease of PLQY of FNs prepared by free radical polymerization was attributed to two factors: (1) generation of defects that can cause nonradiative transitions resulting from QD-ligands desorption and QD-shell oxidation induced by free radicals; (2) self-absorption resulting from aggregation caused by incompatibility of QDs with polymers. Based on these, we proposed a multihierarchical regulation strategy that includes: (1) regulating QD-ligands; (2) precisely controlling free radical concentration; and (3) constructing cross-linked structures of polymer to improve compatibility and to reduce the formation of surface defects. It is crucial to emphasize that the simultaneous coordination of multiple factors is essential. Consequently, a world-record PLQY of 97.6% for FNs was achieved, breaking through the current bottleneck at 65%. The flexible application of this regulatory concept paves the way for the large-scale production of high-brightness QD-polymer complexes, enhancing their potential applications in sensitive biomedical detection.

20.
Front Pediatr ; 12: 1391229, 2024.
Article de Anglais | MEDLINE | ID: mdl-38938505

RÉSUMÉ

Rice body synovitis (RBS) is a rare disease, especially in children. Rheumatoid disorders and tuberculosis are the first two reasons for the formation of the RB. The diagnosis is mainly based on imaging and histopathological features. Herein, we report three cases of RBS in children diagnosed with congenital synovial chondromatosis, tuberculosis (unconfirmed), and ANA -positive juvenile idiopathic arthritis. Clinical features, radiographic findings, pathophysiology, treatment process, and prognosis were reviewed and documented meticulously to enhance cognition in this population and provide some references for clinicians in diagnosing and treating the disease.

SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE