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1.
Int J Biol Macromol ; 269(Pt 2): 132140, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719006

RESUMO

Wounding is one of the most common healthcare problems. Bioactive hydrogels have attracted much attention in first-aid hemostasis and wound healing due to their excellent biocompatibility, antibacterial properties, and pro-healing bioactivity. However, their applications are limited by inadequate mechanical properties. In this study, we first prepared edible rose-derived exosome-like nanoparticles (ELNs) and used them to encapsulate antimicrobial peptides (AMP), abbreviated as ELNs(AMP). ELNs(AMP) showed superior intracellular antibacterial activity, 2.5 times greater than AMP, in in vitro cell infection assays. We then prepared and tested an FDA-approved fibrin-gel of fibrinogen and thrombin encapsulating ELNs(AMP) and novobiocin sodium salt (NB) (ELNs(AMP)/NB-fibrin-gels). The fibrin gel showed a sustained release of ELNs(AMP) and NB over the eight days of testing. After spraying onto the skin, the formulation underwent in situ gelation and developed a stable patch with excellent hemostatic performance in a mouse liver injury model with hemostasis in 31 s, only 35.6 % of the PBS group. The fibrin gel exhibited pro-wound healing properties in the mouse-infected skin defect model. The thickness of granulation tissue and collagen of the ELNs(AMP)/NB-fibrin-gels group was 4.00, 6.32 times greater than that of the PBS group. In addition, the ELNs(AMP)/NB-fibrin-gels reduced inflammation (decreased mRNA levels of TNF-α, IL-1ß, IL6, MCP1, and CXCL1) at the wound sites and demonstrated a biocompatible and biosafe profile. Thus, we have developed a hydrogel system with excellent hemostatic, antibacterial, and pro-wound healing properties, which may be a candidate for next-generation tissue regeneration with a wide clinical application for first-aid hemostasis and infected wound healing.


Assuntos
Antibacterianos , Exossomos , Fibrina , Hemostasia , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Hemostasia/efeitos dos fármacos , Camundongos , Fibrina/química , Antibacterianos/farmacologia , Antibacterianos/química , Exossomos/metabolismo , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Humanos , Infecção dos Ferimentos/tratamento farmacológico , Nanopartículas/química , Géis/química , Hidrogéis/química , Hidrogéis/farmacologia , Masculino
2.
ACS Biomater Sci Eng ; 10(4): 2200-2211, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38447138

RESUMO

In the clinic, inactivation of osteosarcoma using microwave ablation would damage the periosteum, resulting in frequent postoperative complications. Therefore, the development of an artificial periosteum is crucial for postoperative healing. In this study, we prepared an artificial periosteum using silk fibroin (SF) loaded with stromal cell-derived factor-1α (SDF-1α) and calcitonin gene-related peptide (CGRP) to accelerate bone remodeling after the microwave ablation of osteosarcoma. The prepared artificial periosteum showed a sustained release of SDF-1α and CGRP after 14 days of immersion. In vitro culture of rat periosteal stem cells (rPDSCs) demonstrated that the artificial periosteum is favorable for cell recruitment, the activity of alkaline phosphatase, and bone-related gene expression. Furthermore, the artificial periosteum improved the tube formation and angiogenesis-related gene expression of human umbilical vein endothelial cells (HUVECs). In an animal study, the periosteum in the femur of a rabbit was inactivated through microwave ablation and then removed. The damaged periosteum was replaced with the as-prepared artificial periosteum and favored bone regeneration. In all, the designed dual-factor-loaded artificial periosteum is a promising strategy to replace the damaged periosteum in the therapy of osteosarcoma for a better bone-rebuilding process.


Assuntos
Osteossarcoma , Periósteo , Ratos , Humanos , Animais , Coelhos , Quimiocina CXCL12/genética , Quimiocina CXCL12/farmacologia , Peptídeo Relacionado com Gene de Calcitonina , Células Endoteliais , Regeneração Óssea
3.
Nature ; 627(8002): 67-72, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448698

RESUMO

Ordinary metals contain electron liquids within well-defined 'Fermi' surfaces at which the electrons behave as if they were non-interacting. In the absence of transitions to entirely new phases such as insulators or superconductors, interactions between electrons induce scattering that is quadratic in the deviation of the binding energy from the Fermi level. A long-standing puzzle is that certain materials do not fit this 'Fermi liquid' description. A common feature is strong interactions between electrons relative to their kinetic energies. One route to this regime is special lattices to reduce the electron kinetic energies. Twisted bilayer graphene1-4 is an example, and trihexagonal tiling lattices (triangular 'kagome'), with all corner sites removed on a 2 × 2 superlattice, can also host narrow electron bands5 for which interaction effects would be enhanced. Here we describe spectroscopy revealing non-Fermi-liquid behaviour for the ferromagnetic kagome metal Fe3Sn2 (ref. 6). We discover three C3-symmetric electron pockets at the Brillouin zone centre, two of which are expected from density functional theory. The third and most sharply defined band emerges at low temperatures and binding energies by means of fractionalization of one of the other two, most likely on the account of enhanced electron-electron interactions owing to a flat band predicted to lie just above the Fermi level. Our discovery opens the topic of how such many-body physics involving flat bands7,8 could differ depending on whether they arise from lattice geometry or from strongly localized atomic orbitals9,10.

4.
Cell Chem Biol ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38309277

RESUMO

The lysosome-targeting chimera (LYTAC) approach has shown promise for the targeted degradation of secreted and membrane proteins via lysosomes. However, there have been challenges in design, development, and targeting. Here, we have designed a genetically engineered transferrin receptor (TfR)-mediated lysosome-targeting chimera (TfR-LYTAC) that is efficiently internalized via TfR-mediate endocytosis and targets PD-L1 for lysosomal degradation in cultured cells but not in vivo due to short half-life and poor tumor targeting. A delivery platform was developed by fusing TfR-LYTAC to the surface of bacterial outer membrane vesicles (OMVs). The engineered OMV-LYTAC combines PD-1/PD-L1 pathway inhibition with LYTAC and immune activation by bacterial OMVs. OMV-LYTAC significantly reduced tumor growth in vivo. We have provided a modular and simple genetic strategy for lysosomal degradation as well as a delivery platform for in vivo tumor targeting. The study paves the way for the targeting and degradation of extracellular proteins using the TfR-LYTAC system.

5.
Zhongguo Zhong Yao Za Zhi ; 48(22): 5977-5984, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38114203

RESUMO

Plant-derived exosome-like nanoparticles(PELNs) are a class of membranous vesicles with diameters approximately ranging from 30 to 300 nm, isolated from plant tissues. They contain components such as proteins, lipids, and nucleic acids. PELNs play an important role in the metabolism of plant substances and immune defense, and can also cross-regulate the physiological activities of fungi and animal cells, showing significant potential applications. In recent years, research on PELNs has significantly increased, highlighting three main issues:(1) the mixed sources of plant materials for PELNs;(2) the lack of a unified system for isolating and characterizing PELNs;(3) the urgent need to elucidate the molecular mechanisms underlying the cross-regulation of biological functions by PELNs. This article focused on these concerns. It began by summarizing the biological origin and composition of PELNs, discussing the techniques for isolating and characterizing PELNs, and analyzing their biomedical applications and potential future research directions., aiming to promote the establishment of standardized research protocols for PELNs and provide theoretical references for in-depth exploration of the mechanisms underlying PELNs' cross-regulatory effects.


Assuntos
Exossomos , Nanopartículas , Ácidos Nucleicos , Animais , Exossomos/metabolismo , Proteínas/metabolismo , Plantas/metabolismo
6.
Neuroscience ; 534: 29-40, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832908

RESUMO

Neuropathic pain is a debilitating chronic pain condition and is refractory to the currently available treatments. Emerging evidence suggests that melatonin exerts analgesic effects in rodent models of neuropathic pain. Nevertheless, the exact underlying mechanisms of the analgesic effects of melatonin on neuropathic pain are largely unknown. Here, we observed that spinal nerve ligation (SNL) in rats L5 and L6 induced an obvious decrease in the 50% paw withdrawal threshold (PWT) and paw withdrawal latency (PWL), indicating the induction of mechanical allodynia and the hyperalgesia, and melatonin prevented the genesis and maintenance of mechanical allodynia and the hyperalgesia. Notably, the inhibitory action of melatonin on SNL-induced mechanical allodynia and heat hypersensitivity was inhibited by a SIRT1 inhibitor (EX527). Melatonin treatment increased the expression of neuronal sirtuin1 (SIRT1) in DRGs following nerve injury. Furthermore, melatonin treatment restored the injury-dependent decrease in mitochondrial membrane potential and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and reduced the injury-dependent increase in hydrogen peroxide and 8-hydroxy-2-deoxyguanosine (8-OHdG), which was inhibited by EX527. In addition, we found that EX527 impeded the inhibitory effects of melatonin on the SNL-induced increased expression of cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß). In conclusion, the above data demonstrated that melatonin alleviated mechanical allodynia and hyperalgesia induced by peripheral nerve injury via SIRT1 activation. Melatonin resolved mitochondrial dysfunction-oxidative stress-dependent and neuroinflammation mechanisms that were driven by SIRT1 after nerve injury.


Assuntos
Melatonina , Neuralgia , Ratos , Animais , Hiperalgesia/metabolismo , Sirtuína 1/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Ratos Sprague-Dawley , Gânglios Espinais/metabolismo , Neuralgia/metabolismo , Nervos Espinhais/lesões , Mitocôndrias/metabolismo , Analgésicos
7.
J Am Chem Soc ; 145(23): 12920-12927, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37267070

RESUMO

Magnetic interactions in combination with nontrivial band structures can give rise to several exotic physical properties such as a large anomalous Hall effect, the anomalous Nernst effect, and the topological Hall effect (THE). Antiferromagnetic (AFM) materials exhibit the THE due to the presence of nontrivial spin structures. EuCuAs crystallizes in a hexagonal structure with an AFM ground state (Néel temperature ∼ 16 K). In this work, we observe a large topological Hall resistivity of ∼7.4 µΩ-cm at 13 K which is significantly higher than the giant topological Hall effect of Gd2PdSi3 (∼3 µΩ-cm). Neutron diffraction experiments reveal that the spins form a transverse conical structure during the metamagnetic transition, resulting in the large THE. In addition, by controlling the magnetic ordering structure of EuCuAs with an external magnetic field, several fascinating topological states such as Dirac and Weyl semimetals have been revealed. These results suggest the possibility of spintronic devices based on antiferromagnets with tailored noncoplanar spin configurations.

8.
Spine (Phila Pa 1976) ; 48(14): 1009-1016, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37350732

RESUMO

STUDY DESIGN: Retrospective case series. OBJECTIVE: To investigate the accuracy of seven scoring systems for the prediction of survival in lung cancer patients with spinal metastases (SPM). SUMMARY OF BACKGROUND DATA: Although survival scoring systems have been developed for surgical decision-making, the reliability and validity of these models are unclear for specific cancer types. As the prevalence of patients with lung cancer increases, it is imperative to determine the accuracy of these models for lung cancer patients with SPM. MATERIALS AND METHODS: This is a retrospective study of a cohort of lung cancer patients with SPM who underwent spine surgery between 2019 and 2021 at two centers. The optimal area under the curve (AUC) was calculated to evaluate the accuracy of seven candidate scoring systems at 3, 6, and 12 months. Calibration and decision curve analysis was used for further validation. RESULTS: A total of 166 patients (mean age: 58.98±10.94; 105 males and 61 females) with SPM were included. The median postoperative survival was 12.87±0.93 months. The modified Bauer score, revised Tokuhashi score, Linden score, Tomita score, the Skeletal Oncology Research Group nomogram, and the New England Spinal Metastasis Score in prediction survival at 3, 6, and 12 months showed a slightly weaker AUC (range 0.464-0.659). The AUC of the Katagiri-New score in predicting 1-year survival for lung cancer patients was the highest (0.708; range 0.619-0.798). The decision curve analysis showed that the Katagiri-New score led to a greater net benefit than the strategies of changing management for all patients or none of the patients. CONCLUSIONS: This study suggests that the most commonly used models have limitations in predicting survival in patients undergoing spinal surgery for metastatic lung cancer and underestimate survival. In this sample of lung cancer patients, the Katagiri-New Scoring system score had the best performance in predicting 1-year survival. LEVEL OF EVIDENCE: 4.


Assuntos
Neoplasias Pulmonares , Neoplasias da Coluna Vertebral , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Neoplasias da Coluna Vertebral/secundário , Estudos Retrospectivos , Prognóstico , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia
9.
Adv Sci (Weinh) ; 10(13): e2207121, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36828783

RESUMO

Weyl semimetal is a unique topological phase with topologically protected band crossings in the bulk and robust surface states called Fermi arcs. Weyl nodes always appear in pairs with opposite chiralities, and they need to have either time-reversal or inversion symmetry broken. When the time-reversal symmetry is broken the minimum number of Weyl points (WPs) is two. If these WPs are located at the Fermi level, they form an ideal Weyl semimetal (WSM). In this study, intrinsic ferromagnetic (FM) EuCd2 As2 are grown, predicted to be an ideal WSM and studied its electronic structure by angle-resolved photoemission spectroscopy, and scanning tunneling microscopy which agrees closely with the first principles calculations. Moreover, anomalous Hall conductivity and Nernst effect are observed, resulting from the non-zero Berry curvature, and the topological Hall effect arising from changes in the band structure caused by spin canting produced by magnetic fields. These findings can help realize several exotic quantum phenomena in inorganic topological materials that are otherwise difficult to assess because of the presence of multiple pairs of Weyl nodes.

10.
Bioact Mater ; 22: 180-200, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36246664

RESUMO

Rare earth elements (REEs) have been long applied in magnesium alloys, among which the mischmetal-containing WE43 alloy has already got the CE mark approval for clinical application. A considerable amount of REEs (7 wt%) is needed in that multi-phased alloy to achieve a good combination of mechanical strength and corrosion resistance. However, the high complex RE addition accompanied with multiple second phases may bring the concern of biological hazards. Single-phased Mg-RE alloys with simpler compositions were proposed to improve the overall performance, i.e., "Simpler alloy, better performance". The single-phased microstructure can be successfully obtained with typical high-solubility REEs (Ho, Er or Lu) through traditional smelting, casting and extrusion in a wide compositional range. A good corrosion resistance with a macroscopically uniform corrosion mode was guaranteed by the homogeneously single-phased microstructure. The bimodal-grained structure with plenty of sub-grain microstructures allow us to minimize the RE addition to <1 wt%, without losing mechanical properties. The single-phased Mg-RE alloys show comparable mechanical properties to the clinically-proven Mg-based implants. They exhibited similar in-vitro and in-vivo performances (without local or systematic toxicity in SD-rats) compared to a high purity magnesium. In addition, metal elements in our single-phased alloys can be gradually excreted through the urinary system and digestive system, showing no consistent accumulation of RE in main organs, i.e., less burden on organs. The novel concept in this study focuses on the simplification of Mg-RE based alloys for biomedical purpose, and other biodegradable metals with single-phased microstructures are expected to be explored.

11.
J Med Chem ; 65(23): 15738-15748, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36410876

RESUMO

Cancer therapies usually suffer from poor targeting ability and serious side effects. Photoactivatable cancer therapy has the significant advantage of a high spatiotemporal resolution, but most photoactivatable prodrugs require decoration with stoichiometric photocleavable groups, which are only responsive to ultraviolet irradiation and suffer from low reaction efficiency. To tackle these challenges, we herein propose a photoactivation strategy with biogenic riboflavin as the photosensitizer to promote the in situ transformation of noncytotoxic dihydroalkaloid prodrugs dihydrochelerythrine (DHCHE), dihydrosanguinarine (DHSAN), and dihydronitidine (DHNIT) into anticancer alkaloid drugs chelerythrine (CHE), sanguinarine (SAN), and nitidine (NIT), respectively, which can efficiently kill cancer cells and inhibit in vivo tumor growth. Meanwhile, the photoactivatable transformation can be in situ monitored by green-to-red fluorescence conversion, which will contribute to easy controlling of the therapeutic dose. The proposed photoactivatable transformation mechanism was also explored by density functional theory (DFT) calculations. We believe this riboflavin-promoted and imaging-guided photoactivation strategy is promising for precise cancer therapy.


Assuntos
Neoplasias , Pró-Fármacos , Pró-Fármacos/farmacologia , Neoplasias/tratamento farmacológico
12.
ACS Appl Mater Interfaces ; 14(42): 47369-47384, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36228174

RESUMO

Bone implants with the photothermal effect are promising for the treatment of bone tumor defects. Noble metal-based photothermal nanoagents are widely studied for their stable photothermal effect, but they are expensive and difficult to directly grow on implant surfaces. In contrast, non-noble metal photothermal nanoagents are economical but unstable. Herein, to develop a stable and economical photothermal film on bone implants, a Ni nanoparticle-doped oxide semiconductor film was grown in situ on Nitinol via the reduction of Ni-Ti-layered double hydroxides. Ni nanoparticles remained stable in the NiTiO3 structure even when immersed in fluid for 1 month, and thus, the film presented a reliable photothermal effect under near-infrared light irradiation. The film also showed excellent in vitro and in vivo antitumor performance. Moreover, the nanostructure on the film allowed bone differentiation of mouse embryo cells (C3H10T1/2), and the released Ni ions supported the angiogenesis behavior of human vein endothelial cells. Bone implantation experiments further showed the enhancement of osteointegration of the modified Nitinol implant in vivo. This novel multifunctional Nitinol bone implant design offers a promising strategy for the therapy of bone tumor-related defects.


Assuntos
Neoplasias Ósseas , Nanopartículas Metálicas , Nanopartículas , Humanos , Camundongos , Animais , Óxidos , Células Endoteliais , Regeneração Óssea , Neoplasias Ósseas/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Nanopartículas/química , Hidróxidos , Semicondutores
13.
Nanoscale ; 14(28): 10067-10074, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35791918

RESUMO

Band structure engineering has a strong beneficial impact on thermoelectric performance, where theoretical methods dominate the investigation of electronic structures. Here, we use angle-resolved photoemission spectroscopy (ARPES) to analyze the electronic structure and report on the thermoelectric transport properties of half-Heusler TiCoSb high-quality single crystals. High degeneracy of the valence bands at the L and Γ band maximum points was observed, which provides a band-convergence scenario for the thermoelectric performance of TiCoSb. Previous efforts have shown how crystallographic defects play an important role in TiCoSb transport properties, while the intrinsic properties remain elusive. Using hard X-ray photoelectron spectroscopy (HAXPES), we discard the presence of interstitial defects that could induce in-gap states near the valence band in our crystals. Contrary to polycrystalline reports, intrinsic TiCoSb exhibits p-type transport, albeit defects still affect the carrier concentration. In two initially identical p-type TiCoSb crystal batches, distinct metallic and semiconductive behaviors were found owing to defects not noticeable by elemental analysis. A varying Seebeck effective mass is consistent with the change at the Fermi level within this band convergence picture. This report tackles the direct investigation of the electronic structure of TiCoSb and reveals new insights and the strong impact of point defects on the optimization of thermoelectric properties.

14.
Regen Biomater ; 9: rbac027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592137

RESUMO

Macrophages play a vital role for guiding the fate of osteogenesis- related cells. It is well known that nano-topography and bioactive ions can directly enhance osteogenic behavior. However, the effects of nano-structure combined with bioactive ions release on macrophage polarization and the following osteogenesis and angiogenesis are rarely reported. Herein, Mg(OH)2 films with nano-sheet structures were constructed on the surface of Ti using hydrothermal treatment. The film presented nano-sheet topography and sustained release of Mg ions. The results of in vitro culture of bone marrow-derived macrophages (BMDMs), including PCR, western blot and flow cytometry suggested that the nano-Mg(OH)2 films were more favorable for macrophages polarizing to tissue healing M2 phenotype. Moreover, air-pouch model confirmed that the nano-Mg(OH)2 film coated Ti would induce milder inflammation and thinner fibrous layer in vivo, compared with untreated Ti. Furthermore, macrophages-conditioned culture mediums were collected from nano-Mg(OH)2 coated Ti group was superior for the osteogenic behaviors of mice bone marrow stem cells and the angiogenic behaviors of human umbilical vein endothelial cells. With harmonious early inflammatory response and subsequently improved osteogenesis and angiogenesis, the nano-Mg(OH)2 coated Ti is promising for orthopedic applications.

15.
Langmuir ; 38(18): 5381-5391, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35467866

RESUMO

Tumor acidic environment-activated combination therapy holds great promise to significantly decrease side effects, circumvent multiple drug resistance, and improve therapeutic outcomes for cancer treatment. Herein, Sorafenib/ZnPc(PS)4@FeIII-TA nanoparticles (SPFT) are designed with acid-environment turned-on fluorescence to report the activation of triple therapy including photodynamic, chemodynamic, and chemotherapy on hepatocellular carcinoma. The SPFT are composed of SP cores formulated via self-assembly of sorafenib and ZnPc(PS)4, with high drug loading efficiency, and FeIII-TA shells containing FeCl3 and tannic acid. Importantly, the nanoparticles suppress reactive oxygen species (ROS) generation of ZnPc(PS)4 due to their formation in nanoparticles, while assisting simultaneous uptake of the uploaded drugs in cancer cells. The tumor acidic environment initiates FeIII-TA decomposition and accelerates a chemodynamic reaction between FeII and H2O2 to generate toxic •OH. Then, the SP core is decomposed to separate ZnPc(PS)4 and sorafenib, which leads to fluorescence turning-on of ZnPc(PS)4, expedited photodynamic reactions, and burst release of sorafenib. Notably, SPFT shows low dark cytotoxicity to normal cells but exerts high potency on hepatocellular carcinoma cells under near-infrared light irradiation, which is much more potent than either sorafenib or ZnPc(PS)4 alone. This research offers a facile nanomedicine design strategy for cancer therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Fotoquimioterapia , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Compostos Férricos , Fluorescência , Humanos , Peróxido de Hidrogênio , Neoplasias Hepáticas/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Sorafenibe/farmacologia
16.
Microvasc Res ; 142: 104348, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35245516

RESUMO

BACKGROUND: Retinoblastoma protein (Rb) supports vasoprotective E2F Transcription Factor 1 (E2f1)/Dihydrofolate Reductase (Dhfr) pathway activity in endothelial cells. Cyclin I (Ccni) promotes Cyclin-Dependent Kinase-5 (Cdk5)-mediated Rb phosphorylation. Therefore, we hypothesized that endothelial Ccni may regulate cardiovascular homeostasis, vessel remodeling, and abdominal aortic aneurysm (AAA) formation. METHODS: Aortic CCNI mRNA expression was analyzed in the Gene Expression Omnibus (GEO) GSE57691 cohort consisting of AAA patients (n = 39) and healthy controls (n = 10). We employed wild-type (WT) mice and endothelial Ccni knockout (Ccnifl/flTie2-Cre) mice to conduct in vivo and ex vivo experimentation using an Angiotensin (Ang) II hypertension model and a CaCl2 AAA model. Mice were assessed for Rb/E2f1/Dhfr signaling, biopterin (i.e., biopterin [B], dihydrobiopterin [BH2], and tetrahydrobiopterin [BH4]) production, cardiovascular homeostasis, vessel remodeling, and AAA formation. RESULTS: Aortic CCNI mRNA expression was downregulated in AAA patients. Both Ang II- and CaCl2-induced WT mice showed aortic Ccni upregulation coupled with vasculoprotective upregulation of Rb/E2f1/Dhfr signaling and biopterins. Endothelial Ccni knockout downregulated medial Rb/E2f1/Dhfr signaling and biopterins in Ang II-induced hypertensive mice, which exacerbated eNos uncoupling and H2O2 production. Endothelial Ccni knockout impaired in vivo hemodynamic responses and endothelium-dependent vasodilatation in ex vivo mesenteric arteries in response to Ang II. Endothelial Ccni knockout exacerbated mesenteric artery remodeling and AAA risk in response to Ang II and CaCl2. CONCLUSIONS: Endothelial Ccni acts as a critical negative regulator of eNos uncoupling-mediated ROS generation and thereby reduces vulnerability to hypertension-induced vascular remodeling and AAA development in mice.


Assuntos
Angiotensina II , Aneurisma da Aorta Abdominal , Hipertensão , Remodelação Vascular , Angiotensina II/farmacologia , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/prevenção & controle , Biopterinas/metabolismo , Cloreto de Cálcio/metabolismo , Ciclina I/metabolismo , Proteína Rica em Cisteína 61/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Endotélio/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Hipertensão/genética , Hipertensão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo
17.
Biomaterials ; 282: 121408, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35189460

RESUMO

The induction of a suitable immune microenvironment by implant is essential for fast bone regeneration. Surface potential is a critical factor that influences immune cells behavior. We apply polydopamine coatings on a titanium (Ti) surface to decrease its surface potential. A lower surface potential favored the expression of adhesion-related genes in bone marrow-derived monocytes (BMDMs) by activating the focal adhesion kinase signaling pathway. A lower negative surface potential results in higher electronic repulsion between the surface and the BMDMs, because the cells exhibit negative charged membrane. To resist the repulsive force, Integrin ß1 and Integrin ß3 in the cell membrane for low surface potential group are upregulated. Furthermore, BMDMs cultured on Ti with low surface potential are more inclined polarize towards anti-inflammatory phenotype (M2) in vitro and in vivo. Whole gene expression analysis reveals that inhibition of the PI3K-Akt-mTOR signaling axis is responsible for the immune regulation ability of Ti with low surface potential. The cytokines secreted by M2 BMDMs promote osteogenic differentiation of a mouse embryo cell line (C3H10T1/2) and increase osteointegration between the implant and newly formed bone. These findings reveal that surface potential regulation is a promising strategy to reprogram the immune microenvironment for bone regeneration and provide insights into developing biomaterials with immunomodulatory functions.


Assuntos
Osteogênese , Fosfatidilinositol 3-Quinases , Animais , Regeneração Óssea , Diferenciação Celular , Camundongos , Propriedades de Superfície , Titânio/farmacologia
18.
Biomaterials ; 283: 121438, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35220020

RESUMO

Bioactive glass nanoparticles (BGN) have attracted increasing attention for their use in bone tissue repair owing to their special osteogenic activity; however, the underlying molecular mechanism remains unclear. In this study, we report a new mechanism by which BGN regulate bone loss in an osteoporosis mouse model. We found that BGN induced the expression of extracellular vesicles secreted by bone marrow mesenchymal stem cells (BGN + BMSC-EVs), which can inhibit osteoclast differentiation in vitro. Furthermore, our results showed that BGN + BMSC-EVs were rich in the long non-coding RNA NRON, which can inhibit the nuclear translocation of NFATc1 by binding to the nuclear factor of activated T cells transcription factors, thereby inhibiting osteoclast differentiation. We validated the function and biological safety of BGN + BMSC-EVs in an ovariectomized mouse model of osteoporosis. The results of in vivo studies showed that BGN + BMSC-EVs could alleviate bone loss in osteoporotic mice, restore the mechanical properties of mouse femurs, and improve the biochemical indicators in the peripheral blood for bone metabolism in mice, with little to no acute, systemic toxicity. This study may provide a new explanation for the role of BGN in inhibiting osteoclast differentiation and relieving bone loss; additionally, the study findings reveal a promising strategy for the treatment of bone resorption disorders.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Nanopartículas , Osteoporose , RNA Longo não Codificante , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular , Vesículas Extracelulares/metabolismo , Camundongos , Osteoclastos/metabolismo , Osteogênese , Osteoporose/metabolismo , Osteoporose/terapia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
19.
Nat Mater ; 21(2): 203-209, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34811495

RESUMO

A large anomalous Nernst effect (ANE) is crucial for thermoelectric energy conversion applications because the associated unique transverse geometry facilitates module fabrication. Topological ferromagnets with large Berry curvatures show large ANEs; however, they face drawbacks such as strong magnetic disturbances and low mobility due to high magnetization. Herein, we demonstrate that YbMnBi2, a canted antiferromagnet, has a large ANE conductivity of ~10 A m-1 K-1 that surpasses large values observed in other ferromagnets (3-5 A m-1 K-1). The canted spin structure of Mn guarantees a non-zero Berry curvature, but generates only a weak magnetization three orders of magnitude lower than that of general ferromagnets. The heavy Bi with a large spin-orbit coupling enables a large ANE and low thermal conductivity, whereas its highly dispersive px/y orbitals ensure low resistivity. The high anomalous transverse thermoelectric performance and extremely small magnetization make YbMnBi2 an excellent candidate for transverse thermoelectrics.

20.
J Cancer Res Ther ; 18(7): 1845-1854, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36647941

RESUMO

Spinal metastases are the most common source of morbidity in patients with cancer. Recently, microwave ablation has produced satisfactory results in the management of spinal metastases. However, there is still controversy in terms of clinical treatment, such as indication, power, time, and temperature. To standardize the application of microwave ablation technology and reduce the risk of surgical-related complications in spinal metastases, in this report, we aimed to summarize the current evidence and clinical experience of microwave ablation and developed a clinical guideline, initiated by the Musculoskeletal Tumor Group of the Committee for Minimally Invasive Therapy in Oncology of the Chinese Anti-Cancer Association. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used in to rate the quality of evidence and the strength of recommendations, and the Reporting Items for Practice Guidelines in Healthcare (RIGHT) checklist was strictly followed to report the guideline. Finally, 15 evidence-based recommendations were formulated based on the 15 most concerned clinical questions among orthopedic surgeons, oncologists, and interventional radiologists in China. This guideline aims to promote the science-based normalization of microwave ablation for the treatment of spinal metastases.


Assuntos
Ablação por Cateter , Ablação por Radiofrequência , Neoplasias da Coluna Vertebral , Humanos , Ablação por Cateter/métodos , Micro-Ondas/uso terapêutico , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Neoplasias da Coluna Vertebral/secundário
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