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1.
Nano Lett ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739551

RESUMEN

The Dzyaloshinskii-Moriya interaction (DMI) is understood to be forbidden by the symmetry of centrosymmetric systems, thus restricting the candidate types for investigating many correlated physical phenomena. Here, we report the hidden DMI existing in centrosymmetric magnets driven by the local inversion symmetry breaking of specific spin sublattices. The opposite DMI spatially localized on the inverse spin sublattice favors the separated spin spiral with opposite chirality. Furthermore, we elucidate that hidden DMI widely exists in many potential candidates, from the first-principles calculations on the mature crystal database. Interestingly, novel topological spin configurations, such as the anti-chirality-locked merons and antiferromagnetic-ferromagnetic meron chains, are stabilized as a consequence of hidden DMI. Our understanding enables the effective control of DMI by symmetry operations at the atomic level and enlarges the range of currently useful magnets for topological magnetism.

2.
Phys Chem Chem Phys ; 26(7): 6189-6195, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38305045

RESUMEN

Magnetic skyrmions and their effective manipulations are promising for the design of next-generation information storage and processing devices, due to their topologically protected chiral spin textures and low energy cost. They, therefore, have attracted significant interest from the communities of condensed matter physics and materials science. Herein, based on density functional theory (DFT) calculations and micromagnetic simulations, we report the spontaneous 2 nm-diameter magnetic skyrmions in the monolayer CuCrP2Te6 originating from the synergistic effect of broken inversion symmetry and strong Dzyaloshinskii-Moriya interactions (DMIs). The creation and annihilation of magnetic skyrmions can be achieved via the ferroelectric to anti-ferroelectric (FE-to-AFE) transition, due to the variation of the magnetic parameter D2/|KJ|. Moreover, we also found that the DMIs and Heisenberg isotropic exchange can be manipulated by bi-axial strain, to effectively enhance skyrmion stability. Our findings provide feasible approaches to manipulate the skyrmions, which can be used for the design of next-generation information storage devices.

3.
BMC Med Imaging ; 24(1): 127, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822240

RESUMEN

BACKGROUND: The presence of infarction in patients with unrecognized myocardial infarction (UMI) is a critical feature in predicting adverse cardiac events. This study aimed to compare the detection rate of UMI using conventional and deep learning reconstruction (DLR)-based late gadolinium enhancement (LGEO and LGEDL, respectively) and evaluate optimal quantification parameters to enhance diagnosis and management of suspected patients with UMI. METHODS: This prospective study included 98 patients (68 men; mean age: 55.8 ± 8.1 years) with suspected UMI treated at our hospital from April 2022 to August 2023. LGEO and LGEDL images were obtained using conventional and commercially available inline DLR algorithms. The myocardial signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and percentage of enhanced area (Parea) employing the signal threshold versus reference mean (STRM) approach, which correlates the signal intensity (SI) within areas of interest with the average SI of normal regions, were analyzed. Analysis was performed using the standard deviation (SD) threshold approach (2SD-5SD) and full width at half maximum (FWHM) method. The diagnostic efficacies based on LGEDL and LGEO images were calculated. RESULTS: The SNRDL and CNRDL were two times better than the SNRO and CNRO, respectively (P < 0.05). Parea-DL was elevated compared to Parea-O using the threshold methods (P < 0.05); however, no intergroup difference was found based on the FWHM method (P > 0.05). The Parea-DL and Parea-O also differed except between the 2SD and 3SD and the 4SD/5SD and FWHM methods (P < 0.05). The receiver operating characteristic curve analysis revealed that each SD method exhibited good diagnostic efficacy for detecting UMI, with the Parea-DL having the best diagnostic efficacy based on the 5SD method (P < 0.05). Overall, the LGEDL images had better image quality. Strong diagnostic efficacy for UMI identification was achieved when the STRM was ≥ 4SD and ≥ 3SD for the LGEDL and LGEO, respectively. CONCLUSIONS: STRM selection for LGEDL magnetic resonance images helps improve clinical decision-making in patients with UMI. This study underscored the importance of STRM selection for analyzing LGEDL images to enhance diagnostic accuracy and clinical decision-making for patients with UMI, further providing better cardiovascular care.


Asunto(s)
Medios de Contraste , Aprendizaje Profundo , Infarto del Miocardio , Humanos , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Masculino , Femenino , Estudios Prospectivos , Gadolinio , Relación Señal-Ruido , Anciano , Imagen por Resonancia Magnética/métodos
4.
Artículo en Inglés | MEDLINE | ID: mdl-38466062

RESUMEN

Objective: To assess the effectiveness of using mobile health platforms for continuous care in preventing and treating osteoporosis. Methods: 114 patients with osteoporosis admitted to Nantong First People's Hospital from March 2021 to June 2022 were recruited and assigned equally via random number table method to receive either routine care (namely education on osteoporosis disease, dietary guidance, exercise guidance, activity guidance, medication supervision, fall prevention, psychological care, and secondary health education at the time of discharge) (routine group) or mobile health platform-based continuity of care (continuity group), with 57 patients in each group. Outcome measures included treatment compliance, disease knowledge of osteoporosis (diet, exercise, risk factors), quality of life level, and care satisfaction. Results: All eligible patients were followed up for one year after discharge from the hospital. Patients with continuity of care showed higher treatment compliance and disease knowledge of diet, exercise, and risk factors than those with routine care (P = .004). Continuity of care was associated with significantly higher MOS 36-item short-form health survey (SF-36) scores (The SF-36 is a self-administered questionnaire containing 36 items that survey overall health status) and nursing satisfaction in patients versus routine care (P = .004). Conclusion: Mobile health platform-based continuity of care effectively enhances post-discharge compliance and knowledge of osteoporosis in patients with osteoporosis, thereby improving post-discharge quality of life and satisfaction with care. Multi-center studies involving diverse healthcare settings and patient populations would provide more robust evidence. Moreover, these findings highlight the potential benefits of incorporating mobile health platforms into the care continuum for osteoporosis patients. Also, by utilizing mobile health platforms, healthcare providers can extend their reach beyond hospital settings and provide continuous care and support to patients, potentially reducing the burden on healthcare systems and improving overall population health outcomes.

5.
J Biol Chem ; 298(10): 102443, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36055408

RESUMEN

Spinal cord injury (SCI) is the most severe result of spine injury, but no effective therapy exists to treat SCI. We have previously shown that the E3 ubiquitin ligase Two RING fingers and DRIL 1 (Triad1) promotes neurite outgrowth after SCI. However, the mechanism by which Triad1 affects neuron growth and the potential involvement of its ubiquitination activity is unclear. Neuroprotective cytokine pleiotrophin (PTN) can promote microglia proliferation and neurotrophic factor secretion to achieve neuroprotection. We find using immunostaining and behavioral assays in rats that the expression of Triad1 and the PTN was peaked at 1 day after SCI and Triad1 improved motor function and histomorphological injury after SCI. We show using flow cytometry and astrocyte/neuronal coculture assays that Triad1 overexpression promoted PTN protein levels, neurotrophic growth factor (NGF) expression, brain-derived neurotrophic factor (BDNF) expression, astrocyte and neuronal viability, and neurite outgrowth but suppressed astrocyte apoptosis, while shRNA-mediated knockdown of Triad1 and PTN had the opposite effects. Ubiquitin ligase murine double mutant 2 (MDM2) has previously been demonstrated to participate in the process of neurite outgrowth and mediate ubiquitination of p53. Furthermore, we demonstrate overexpression of MDM2 downregulated PTN protein levels, NGF expression and BDNF expression in astrocytes, and inhibited neurite outgrowth of neurons. In addition, MDM2 facilitated PTN ubiquitination, which was reversed by Triad1. Finally, we show simultaneous sh-PTN and MDM2 overexpression attenuated the neurite outgrowth-promoting effect of Triad1 overexpression. In conclusion, we propose Triad1 promotes astrocyte-dependent neurite outgrowth to accelerate recovery after SCI by inhibiting MDM2-mediated PTN ubiquitination.


Asunto(s)
Traumatismos de la Médula Espinal , Ubiquitina , Animales , Ratones , Ratas , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Citocinas/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Neuritas/metabolismo , Proyección Neuronal/genética , Neuroprotección , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Expresión Génica
6.
Macromol Rapid Commun ; 44(14): e2300117, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37183270

RESUMEN

Photoresponsive polymers have attracted increasing interest owing to their potential applications in anticounterfeiting, information encryption, adhesives, etc. Among them, diarylethene (DAE)-containing polymers are one of the most promising photoresponsive polymers and have unique thermal stability and fatigue resistance compared to azobenzene- and spiropyran-containing polymers. Herein, the design of DAE-containing polymers based on different types of structures, including main chain polymers, side-chain polymers, and crosslinked polymers, is introduced. The mechanism and applications of DAE-containing polymers in anti-counterfeiting, information encryption, light-controllable adhesives, and photoinduced healable materials are reviewed. In addition, the remaining challenges of DAE-containing polymers are also discussed.


Asunto(s)
Polímeros , Polímeros/química
7.
J Chem Phys ; 159(18)2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37962446

RESUMEN

Effect mechanisms of the undercooling degree and the surface configuration on the ice growth characteristics were revealed under micro-droplets icing conditions. Preferential ice crystals appear firstly on the surfaces due to the randomness of icing, and obtain growth advantages to form protruding structures. Protruding structures block the incoming droplets from contacting the substrates, causing voids around the structures. The undercooling degree mainly affects the density and the growth rate of preferential ice crystals. With the increase of undercooling degree, the preferential ice crystals have higher density and growth rate, resulting in stronger growth advantage and higher porosity. The surface configuration affects the growth mode, and the ice layer grows with uniform mode, spreading mode and structure-induced mode on the aluminum, smooth Polytetrafluoroethylene (PTFE) and rough PTFE surface respectively, causing the needle-like, ridge-like and cluster-like ice crystals. The rough structures effectively improve the porosity of the ice layer, which is beneficial for optimizing the icephobic property of the materials. This paper provides important theoretical guidance for the design of subsequent icephobic materials.

8.
Ecotoxicol Environ Saf ; 251: 114552, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36652741

RESUMEN

The processes of hydraulic fracturing to extract shale gas generate a large amount of wastewater, and the potential impacts of wastewater discharge after treatment are concerning. In this field study, we investigated the effects of the irrigation of paddy fields for 2 consecutive years by river water that has been influenced by shale gas wastewater discharge on soil physicochemical properties, microbial community structure and function, and rice grain quality. The results showed that conductivity, chloride and sulfate ions in paddy soils downstream of the outfall showed an accumulative trend after two years of irrigation, but these changes occurred on a small scale (<500 m). Two-year irrigation did not cause the accumulation of trace metals (barium, cadmium, chromium, copper, lead, strontium, zinc, nickel, and uranium) in soil and rice grains. Among all soil parameters, the accumulation of chloride ions was the most pronounced, with concentrations in the paddy soil at the discharge site 13.3 times higher than at the upstream control site. The use of influenced river water for paddy irrigation positively increased the soil microbial diversity, but these changes occurred after two years of irrigation and did not occur after one year of irrigation. Overall, the use of river water affected by shale gas wastewater discharge for agricultural irrigation has limited effects on agroecosystems over a short period. Nevertheless, the possible negative effects of contaminant accumulation in soil and rice caused by longer-term irrigation should be seriously considered.


Asunto(s)
Microbiota , Oryza , Contaminantes del Suelo , Suelo/química , Aguas Residuales , Gas Natural , Cloruros , Riego Agrícola , Agua , Oryza/química , Contaminantes del Suelo/análisis
9.
J Am Chem Soc ; 144(22): 9707-9714, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35574835

RESUMEN

We developed type-II core-shell nanocrystals (NCs) with a chiral low-dimensional perovskite shell and an achiral 3D MAPbBr3 core. The core-shell NCs exhibit spin-polarized luminescence at the first excitation band of the achiral core, which is due to the chiral-induced spin selectivity (CISS) effect-governed spin-dependent shell-to-core electron transportation and the subsequent electron-hole recombination in the core. The preferred spin state of the transferred electrons is determined by the handness of the chiral shell. For the core-shell NCs film, a photoluminescence quantum yield (PLQY) of 54% and a circularly polarized luminescence (CPL) with a maximum |glum| of 4.0 × 10-3 are obtained at room temperature. Finally, we achieved a spin-polarized light-emitting diode (spin-LED), affording a circularly polarized electroluminescence (CP-EL) with a |gCP-EL|of 6.0 × 10-3 under ambient conditions.

10.
Mol Biol Rep ; 49(7): 6459-6466, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35581507

RESUMEN

Lumbar facet osteoarthritis (FJOA) is a major cause of severe lower back pain and disability worldwide. However, the mechanism underlying cartilage degeneration in FJOA remains unclear. The purpose of this study was to investigate the regulation and mechanism of P2Y12 on chondrocyte apoptosis in FJOA. The experimental rats were randomly divided into non-operation (n = 20) and operation groups (n = 20). In the operation group, Sodium iodoacetate (MIA, Sigma, 200 mg/mL) was injected into the right L4/5 facet process using a blunt nanoneedle 26 (WPI, Sarasota, FL, USA) under the control of an injection pump. The final injection volume was 5µL and the injection rate was 2µL/min. The facet joint was removed four weeks after surgery. After the operation, samples were stored at -80 °C until further use, whereby the right facet joints in each group were tested. Hematoxylin and eosin (HE) and iron-red solid green staining were used to observe the degeneration of articular chondrocytes in rats. Immunohistochemistry and western blotting were used to observe the expressions of P2Y12, Matrix metalloproteinase 13 (MMP13), Collagen II (COL2), and other cartilage degeneration and apoptosis-related genes. Co-localization of P2Y12-cleaved caspase-3 in the apoptosis model was detected by dual-standard immunofluorescence staining. Apoptosis was also detected by flow cytometry and TUNEL assay.P2Y12 is highly expressed in OA cartilage tissue, and inhibits IL-1ß -induced chondrocyte apoptosis through PI3K/AKT signaling pathway, thus playing a certain protective role on cartilage.


Asunto(s)
Condrocitos , Osteoartritis de la Columna Vertebral , Receptores Purinérgicos P2Y12/metabolismo , Animales , Apoptosis , Condrocitos/metabolismo , Osteoartritis de la Columna Vertebral/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Regulación hacia Arriba
11.
Somatosens Mot Res ; 39(1): 21-28, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34641746

RESUMEN

PURPOSE: Spinal cord injury entails a high risk of major disability, but there is still no effective treatment for this condition. This study aims to explore the neuronal apoptosis after spinal cord injury, which is a key component of secondary injury processes, and plays a critical role in the development of neurological dysfunction. MATERIALS AND METHODS: We studied the expression of the E3 ubiquitin ligase Triad1 and its interaction with p53 in the spinal cord after a spinal cord contusion injury in rats. We explored the regulation function of Triad1 to the neuronal apoptosis through p53-caspase3 pathway in primary neurons. RESULTS: Triad1 was markedly up-regulated in the grey matter one day after injury, and the distribution and time point of Triad1 expression correlated with the presence of apoptotic neurons. Co-immunoprecipitation experiments further demonstrated that Triad1 interacted with p53 after spinal cord injury. Specific siRNA and overexpression plasmids for Triad1 were transfected into primary neurons, and the expression of both p53 and caspase3 was altered following the change of Triad1. CONCLUSIONS: These findings indicate that Triad1 is involved in regulating the pathological process of neuronal apoptosis mediated by p53-caspase3 pathway after spinal cord injury.


Asunto(s)
Traumatismos de la Médula Espinal , Ubiquitina-Proteína Ligasas , Animales , Apoptosis , Neuronas/metabolismo , Ratas , Médula Espinal , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
12.
J Cell Mol Med ; 25(11): 4988-5000, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33939240

RESUMEN

Osteoclasts play a critical role in osteoporosis; thus, inhibiting osteoclastogenesis is a therapeutic strategy for osteoporosis. Galangin, a natural bioflavonoid extracted from a traditional Chinese herb, possesses a variety of biological activities, including anti-inflammation and anti-oxidation. However, its effects on osteoporosis have not been elucidated. In this study, we found that galangin treatment dose-dependently decreased osteoclastogenesis in bone marrow-derived macrophages (BMMs). Moreover, during osteoclastogenesis, osteoclast-specific genes, such as tartrate-resistant acid phosphatase (TRAP), cathepsin K (CtsK), ATPase, H + transporting, lysosomal V0 subunit D2 (V-ATPase d2) and dendritic cell-specific transmembrane protein (DC-STAMP), were down-regulated by galangin treatment. Furthermore, the results of the pit formation assay and F-actin ring staining revealed impaired osteoclastic bone resorption in the galangin-treated group compared with that in the control group. Additionally, galangin treatment also inhibited the phosphorylation of p38 and ERK of MAPK signalling pathway, as well as downstream factors of NFATc1, C-Jun and C-Fos. Consistent with our in vitro results, galangin suppressed lipopolysaccharide (LPS)-induced bone resorption via inhibition of osteoclastogenesis. Taken together, our findings provide evidence that galangin is a promising natural compound for the treatment of osteoporosis and may be associated with the inhibition of MAPK and NF-κB signalling pathways.


Asunto(s)
Flavonoides/farmacología , Regulación Neoplásica de la Expresión Génica , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , FN-kappa B/antagonistas & inhibidores , Osteoclastos/efectos de los fármacos , Osteogénesis , Osteoporosis/tratamiento farmacológico , Ligando RANK/metabolismo , Animales , Apoptosis , Proliferación Celular , Células Cultivadas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Osteoclastos/citología , Osteoclastos/metabolismo , Osteoporosis/metabolismo , Osteoporosis/patología , Fosforilación , Ligando RANK/genética
13.
Mamm Genome ; 32(6): 457-465, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34272987

RESUMEN

The heart is one of the most common organs involved in sepsis-induced organ dysfunction and about 50% septic patients complicated with myocardial injury. So far, the molecular mechanisms underlying sepsis-induced cardiac damage remain unclear. In this study we aimed to evaluate the effect of miR-642a on sepsis-induced cardiac injury in vitro and explore the possible lncRNA-microRNA mechanism. We first downloaded GSE101639 to identify differentially expressed genes (DEGs) in sepsis. The expression of miR-642a in LPS-induced H9C2 cells was detected by qRT-PCR. MTT assay, cell migration, flow cytometry analysis, ELISA, qRT-PCR and Western blotting analysis were applied to evaluating the effect of miR-642a mimic on LPS-induced H9C2 cells. The bioinformatics analysis and the rescue experiment were devoted to the underlying mechanism. The results showed miR-642a expression was decreased in septic patients and LPS-induced H9C2 cells. Besides, MiR-642a mimic promoted cell viability and migration, inhibited cell apoptosis of LPS-induced H9C2 cells. Bioinformatics analysis showed miR-642a directly targets with 3'-UTR of ROCK1. Moreover, LUCAT1 regulated ROCK1 expression act as a competing endogenous RNA (ceRNA) for miR-642a. Our data demonstrated that lncRNA LUCAT1 could function via sponging miR-642a to regulate ROCK1 expression in LPS-induced H9C2 cells. And knockdown of lncRNA LUCAT1 could suppress LPS-induced cardiac injury in vitro.


Asunto(s)
MicroARNs , Miocitos Cardíacos , ARN Largo no Codificante , Sepsis , Apoptosis/genética , Técnicas de Silenciamiento del Gen , Humanos , Lipopolisacáridos , MicroARNs/genética , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Sepsis/genética , Sepsis/patología , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/farmacología
14.
Mol Cell Biochem ; 476(4): 1929-1938, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33502650

RESUMEN

Tumor necrosis factor receptor-associated factor 6 (TRAF6), a regulator of NF-κB signaling, has been discovered recently to be probably related to osteoarthritis, while the function of TRAF6 in lumbar facet joint osteoarthritis(FJOA)still remains unknown. The aim of this study was to probe the specific function of TRAF6 in chondrocytes and its connection with the pathophysiology of FJOA. We found upregulation of TRAF6 in FJOA cartilage by western blot analysis. In vitro, we stimulated immortalized human chondrocytes by LPS to establish the cells apoptosis model. Western blot analysis demonstrated that levels of TRAF6 and cleaved caspase-3/8 in the chondrocyte injury model increased significantly. Knockdown of TRAF6 suppressed the expression of matrix metallopeptidase-13 (MMP-13) and interleukin-6 (IL-6) induced by LPS, and alleviated cell apoptosis. Meanwhile, western blot and immunofluorescent staining demonstrated that IκBα degradation and p65 nuclear transportation were also inhibited, revealing that knockdown of TRAF6 suppressed activation of the NF-κB pathway in LPS-induced chondrocytes apoptosis model. Collectively, our findings suggest that TRAF6 plays a crucial role in FJOA development by regulating NF-κB signaling pathway. Knockdown of TRAF6 may supply a potential therapeutic strategy for FJOA.


Asunto(s)
Apoptosis , Condrocitos/metabolismo , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Osteoartritis de la Columna Vertebral/metabolismo , Transducción de Señal , Factor de Transcripción ReIA/metabolismo , Articulación Cigapofisaria/metabolismo , Línea Celular Transformada , Condrocitos/patología , Técnicas de Silenciamiento del Gen , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Osteoartritis de la Columna Vertebral/genética , Osteoartritis de la Columna Vertebral/patología , Factor de Transcripción ReIA/genética , Articulación Cigapofisaria/patología
15.
Phys Chem Chem Phys ; 23(4): 3008-3018, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33480932

RESUMEN

Electric field tailored magnetic properties of the perovskite-type oxide heterostructures are important in spintronic devices with low energy consumption and small size. Here, the electric field modulated magnetic properties of underoxidized SrRuO3 (SRO)/SrTiO3 (STO) heterostructures are investigated using first-principles calculations. The spin polarization of underoxidized SRO/STO heterostructures turns from negative to positive as the electric field changes from -0.2 to 0.2 V nm-1. The underoxidized SRO/STO heterostructure with 7 SRO atomic layers turns from perpendicular magnetic anisotropy to in-plane magnetic anisotropy as the electric field turns from -0.2 to 0.2 V nm-1, which can be attributed to the in-plane dx2-y2 and out-of-plane dxz, dyz orbitals. The Dzyaloshinskii-Moriya interaction of underoxidized SRO/STO heterostructures can also be effectively tailored using an electric field. These results indicate that the use of electric field is an effective method to modulate magnetic properties of perovskite-type oxide heterostructures, which is beneficial for the development of the high-performance spintronic devices.

16.
Somatosens Mot Res ; 38(4): 339-346, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34553673

RESUMEN

PURPOSE: Low back pain (LBP) is a long-lasting and chronic symptom without any exact cause. This study attempts to propose a new staging system based on the original grading system combined with pathological results and clinical symptoms to better clarify the dynamic evolution of LBP related to cartilage degeneration during facet joint osteoarthritis (FJOA). To explore a potential target for diagnosis, treatment, and drug intervention of facet joint osteoarthritis related LBP via protecting chondrocytes. MATERIALS AND METHODS: All the facet joints were divided into 4 groups according to our new degenerative staging system based on Weishaupt grade, CT and MRI. Collect the facet joint samples from patients whom suffered lumbar fusion surgery for lumbar disc herniation. Molecular biology experiments were used to explore the effect of Wnt16 on the degeneration of facet joints. Micro-CT examination and pain stimulation test checked the biological function of Wnt16 in rats. RESULTS: Wnt16 was significantly increased and more aggregated in the facet joint chondrocytes in the Phase III and Phase IV, which is consistent with the pathological findings of cartilage degeneration (OARSI). We found that Wnt16 participated in the regulation of FJOA via Wnt/ß-catenin pathway in vitro, which was inhibited by specific inhibitor DKK1. The rats, rich expressed Wnt16, showed higher paw withdrawal thresholds and prolonged paw withdrawal latency to FJOA related LBP. Micro-CT examination for the lumbar spine of rats showed Wnt16 protected the chondrocytes from FJOA. CONCLUSIONS: This study defined a new staging system for LBP related cartilage degeneration of facet joint based on the original grading system combined with pathological results and clinical symptoms. Wnt16 is expected to be a potential target for treatment of FJOA via protecting chondrocytes.


Asunto(s)
Dolor de la Región Lumbar , Osteoartritis , Articulación Cigapofisaria , Animales , Condrocitos , Humanos , Vértebras Lumbares , Osteoartritis/complicaciones , Ratas , Proteínas Wnt , Articulación Cigapofisaria/diagnóstico por imagen , beta Catenina
17.
FASEB J ; 33(8): 9100-9115, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31050917

RESUMEN

Postmenopausal osteoporosis is the most common form of primary osteoporosis, and the incidence of the condition is rapidly increasing. In consideration of the limitations of current therapeutic options for the treatment of postmenopausal osteoporosis, there is an urgent need to develop safer alternatives. Anacardic acid, a natural phenolic acid compound extracted from cashew nut shell, possesses potent antitumor and anti-inflammatory effects and inhibits NF-κB signaling. However, its effect on osteoclasts remains unknown. This study reports the first evidence for the antiosteoclastogenic and antiresorptive effects of anacardic acid on bone marrow-derived macrophage-derived osteoclasts. Mechanistically, anacardic acid disrupts the phosphorylation of TGF-ß activated kinase 1 and subsequently suppresses multiple receptor activator of NF-κB ligand-induced signaling cascades, ultimately inhibiting the induction and activation of the crucial osteoclast transcriptional factor nuclear factor of activated T-cell cytoplasmic 1. Consistent with cellular results in vitro, anacardic acid treatment improves bone density in the murine model of ovariectomy-induced bone loss. Taken together, our study provides promising evidence for the therapeutic application of anacardic acid as a new potential pharmacological treatment for osteoporosis.-Zhao, K., Jia, Y., Peng, J., Pang, C., Zhang, T., Han, W., Jiang, J., Lu, X., Zhu, J., Qian, Y. Anacardic acid inhibits RANKL-induced osteoclastogenesis in vitro and prevents ovariectomy-induced bone loss in vivo.


Asunto(s)
Ácidos Anacárdicos/farmacología , Resorción Ósea/tratamiento farmacológico , Osteoclastos/efectos de los fármacos , Ligando RANK/metabolismo , Células 3T3 , Transporte Activo de Núcleo Celular , Animales , Resorción Ósea/etiología , Resorción Ósea/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Técnicas In Vitro , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patología , Osteogénesis/efectos de los fármacos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/patología , Ovariectomía/efectos adversos , Células RAW 264.7 , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo
18.
Phys Chem Chem Phys ; 22(41): 23597-23608, 2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33057488

RESUMEN

Two-dimensional (2D) Janus materials are a novel kind of 2D materials, which have potential applications in nanoelectronics, optoelectronics and spintronics. However, a 2D Janus material combined with intrinsic ferromagnetism, electric dipole moment, valley polarization and Dzyaloshinskii-Moriya interaction (DMI) remains rarely reported. Here, the electronic structure and magnetic properties of 2D intrinsic ferromagnetic Janus 2H-VSeX (X = S, Te) monolayers are investigated systematically using the density-functional theory. Janus 2H-VSeX (X = S, Te) monolayers are intrinsic ferromagnetic semiconductors with in-plane magnetic anisotropy (IMA). The valley splitting of Janus 2H-VSeX (X = S, Te) monolayers appears by considering the spin-orbit coupling (SOC) effect and out of plane magnetization. Additionally, spontaneous vertical electric dipole moment and a large DMI are also found in Janus 2H-VSeX (X = S, Te) monolayers due to the broken inversion symmetry. Moreover, the valley splitting and DMI can be significantly increased by applying in-plane biaxial strain. These results provide an interesting 2D intrinsic ferromagnetic Janus material, which has potential applications in spintronic and valleytronic devices.

19.
J Cell Physiol ; 234(10): 17549-17560, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30793311

RESUMEN

Osteolytic diseases are characterized by an increase in the number and/or activity of bone-resorbing osteoclasts. Identification of natural compounds that can suppress osteoclast formation and function is crucial for the prevention and treatment of osteolytic diseases. Vitexin, a naturally-derived flavonoid extracted from various medicinal plant species, demonstrates a broad range of pharmacological properties including anticancer and anti-inflammatory effects. Here in this study, we showed that vitexin exerts antiosteoclastogenic effects by directly inhibiting receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation and bone resorption in vitro and protected against lipopolysaccharide (LPS)-induced inflammatory osteolysis in vivo. Vitexin suppressed the early activation of ERK and p38 MAPK pathways in response to RANKL thereby attenuating the downstream induction of c-Fos and NFATc1, and abrogating the expression of osteoclast marker genes. Collectively, these results provide evidence for the therapeutic application of vitexin in the treatment of osteoclast-mediated bone lytic diseases.


Asunto(s)
Apigenina/farmacología , Osteogénesis/efectos de los fármacos , Osteólisis/prevención & control , Ligando RANK/antagonistas & inhibidores , Actinas/metabolismo , Animales , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/fisiología , Células Cultivadas , Técnicas In Vitro , Lipopolisacáridos/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteogénesis/fisiología , Osteólisis/inducido químicamente , Osteólisis/metabolismo , Ligando RANK/metabolismo
20.
J Cell Physiol ; 234(5): 7498-7509, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30471112

RESUMEN

Osteoclasts (OCs) are multinuclear giant cells responsible for bone resorption, and an excessive bone resorption by OCs plays an important role in osteoporosis. Commonly used drugs for the treatment of osteoporosis have severe side effects. As such, identification of alternative treatments is essential. Garcinol, a polyisoprenylated benzophenone extracted from the fruit of Garcinia indica, has shown a strong antitumor effect through the nuclear factor-κB (NF-κB) and mitogen-associated protein kinases (MAPK) signaling pathways. However, the role of garcinol in the osteoclastogenesis is still unclear. Here, we demonstrated that garcinol can inhibit the receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis, osteoclastogenesis-related gene expression, the f-actin ring, and resorption pit formation. In addition, garcinol abrogated RANKL-induced osteoclastogenesis by attenuating the degradation of the MAPK, NF-κB, and PI3K-AKT signaling pathway as well as downstream factors c-jun, c-fos, and NFATC1. In vivo, suppression of osteoclastogenesis by garcinol was evidenced by marked inhibition of lipopolysaccharide-induced bone resorption. In conclusion, our data demonstrated that garcinol inhibited the RANKL-induced osteoclastogenesis by suppressing the MAPK, NF-κB, and PI3K-AKT signaling pathways and thus has potential as a novel therapeutic option for osteolytic bone diseases.


Asunto(s)
Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ligando RANK/metabolismo , Terpenos/farmacología , Animales , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Línea Celular , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Factores de Transcripción NFATC/metabolismo , Osteoclastos/metabolismo , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-fos/metabolismo , Transducción de Señal/efectos de los fármacos
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