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1.
Front Plant Sci ; 15: 1344972, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425798

RESUMO

Over the past several decades, a decreasing trend in solar radiation has been observed during the wheat growing season. The effects of shade stress on grain yield formation have been extensively studied. However, little information on shade stress's effects on protein formation warrants further investigation. Two wheat cultivars were grown under three treatments, no shade as the control group (CK), shading from the joint to the anthesis stage (S1), and shading from the joint to the mature stage (S2), to investigate the effects of shade stress on the free amino acids of the caryopsis and endosperm and protein accumulation during grain filling. The dry mass of caryopsis and endosperm was significantly decreased under shade stress, whereas Glu, Ser, Ala, and Asp and protein relative content increased during grain filling. The observed increases in total protein in S1 and S2 were attributed to the increases in the SDS-isoluble and SDS-soluble protein extracts, respectively. S1 improved polymer protein formation, but S2 delayed the conversion of albumins and globulins into monomeric and polymeric proteins. Moreover, shade stress increased the proportion of SDS-unextractable polymeric protein, which represented an increase in the degree of protein polymerization. The polymerization of protein interrelations between protein components and accumulation in caryopsis and endosperm provided novel insights into wheat quality formation under shade stress.

2.
Food Chem ; 444: 138667, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38335686

RESUMO

Iron-copper nanozymes (Fe-Cu NZs) with good peroxidase activity were prepared through hydrothermal method by using copper nitrate as copper source, iron acetate as iron source and 2, 5-dihydroxyterephthalic acid as organic ligand. Upon oxidation of the colourless TMB to light blue products by Fe-Cu NZs, the addition of Norfloxacin (NOR) resulted in a colour change to dark blue. The absorbance of the system correlated linearly with NOR concentration in the range of 3.3 µM to 66 µM, and the detection limit (LOD) was 0.386 µM. A rapid colourimetric assay for the determination of NOR in food matrices was developed, with a detection time of only one minute. Additionally, the assay facilitated the simultaneous catalytic degradation of NOR via Fe-Cu NZs. The primary degradation mechanism of NOR was identified as the transformation of the quinolone ring and the cleavage of the C9 = C10 double bond, which was substantiated by high-performance liquid chromatography (HPLC).


Assuntos
Norfloxacino , Quinolonas , Ferro/química , Cobre/química , Antioxidantes , Colorimetria/métodos , Peróxido de Hidrogênio
3.
Nanomaterials (Basel) ; 14(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38334583

RESUMO

Recently, it has been reported that the skyrmion Hall effect can be suppressed in an elliptical skyrmion-based device. Given that defects are unavoidable in materials, it is necessary and important to investigate the dynamics of an elliptical skyrmion in a defective racetrack device. In this work, the current-driven dynamics of an elliptical skyrmion in a defective racetrack device are systematically studied using micromagnetic simulations. The system energy analysis reveals that the magnetic parameters of the circular defect play critical roles in determining the type (repulsive or attractive) and the magnitude of the force on the elliptical skyrmion. The simulated trajectories show that the primary motion modes of the elliptical skyrmion in the defective racetrack can be divided into four types, which are dependent on the values of the Dzyaloshinskii-Moriya interaction (DMI) constant Dd, the perpendicular magnetic anisotropy constant Kd, the magnitude of the driving current density J, and the size d of the defect. Further investigation of the motion-mode phases of the skyrmion reveals the synthetic effects of Dd, Kd, J, and d. Finally, the minimum depinning current density J, which linearly depends on the parameters of Dd and Kd, is obtained for a skyrmion completely pinned in the defect. Our findings give insights into the dynamics of an elliptical skyrmion in the presence of a defect with different magnetic parameters in a racetrack device and may be useful for performance enhancement of skyrmion-based racetrack memory devices.

4.
Nanoscale ; 16(9): 4866-4871, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38315558

RESUMO

Owing to its stable graphene-like honeycomb structure, suitable band gap, and nontoxicity, SnC monolayer (ML) has attracted increasing attention in photocatalytic applications. One pertinent obstacle inherent to SnC ML-based photocatalysts has been the high energy barrier in hydrogen evolution reaction (HER) that always requires external energy input and/or strongly acidic conditions. Herein, we propose a two-dimensional (2D) SnC/ZrS2 van der Waals heterostructure (vdWHS) for highly efficient photocatalytic water splitting using first-principles calculations. The results show that the pristine vdWHS is an S-scheme heterostructure that works in acidic conditions for water splitting owing to the high energy barrier in HER. Notably, detailed further investigations show that doping Si in the SnC ML of the vdWHS can solve this high barrier problem, leading to a high-performance low-cost photocatalyst. Our work offers a convenient strategy to solve the notorious high barrier problem in HER that often troubles the SnC ML and other 2D materials such as transition metal dichalcogenide MLs for the design and fabrication of highly efficient photocatalysts.

5.
Toxics ; 12(2)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38393225

RESUMO

Cobalt alloys have numerous applications, especially as critical components in orthopedic biomedical implants. However, recent investigations have revealed potential hazards associated with the release of nanoparticles from cobalt-based implants during implantation. This can lead to their accumulation and migration within the body, resulting in adverse reactions such as organ toxicity. Despite being a primary interface for cobalt nanoparticle (CoNP) exposure, skeletal muscle lacks comprehensive long-term impact studies. This study evaluated whether selenium nanoparticles (SeNPs) could mitigate CoNP toxicity in muscle cells and zebrafish models. CoNPs dose-dependently reduced C2C12 viability while elevating reactive oxygen species (ROS) and apoptosis. However, low-dose SeNPs attenuated these adverse effects. CoNPs downregulated myogenic genes and α-smooth muscle actin (α-SMA) expression in C2C12 cells; this effect was attenuated by SeNP cotreatment. Zebrafish studies confirmed CoNP toxicity, as it decreased locomotor performance while inducing muscle injury, ROS generation, malformations, and mortality. However, SeNPs alleviated these detrimental effects. Overall, SeNPs mitigated CoNP-mediated cytotoxicity in muscle cells and tissue through antioxidative and antiapoptotic mechanisms. This suggests that SeNP-coated implants could be developed to eliminate cobalt nanoparticle toxicity and enhance the safety of metallic implants.

6.
Anal Methods ; 16(7): 1012-1020, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38304962

RESUMO

Isoniazid is a first-line drug used to treat tuberculosis. However, its excessive use can lead to serious adverse effects. Thus, strict monitoring of the isoniazid levels in medications and human systems is required. In this study, a new polymer (AlPc-TB POP) containing a metal phthalocyanine and Tröger's base was synthesized and explored as an electrocatalyst for the oxidation of isoniazid. The results indicated that the polymer is an excellent electron-transfer medium for isoniazid oxidation. The AlPc-TB POP-based sensor quantified isoniazid in the linear range of 0.1-130 µM, with a detection limit of 0.0185 µM. The response of the developed sensor to isoniazid was reproducible and stable. Furthermore, this method can accurately determine isoniazid levels by ignoring the influence of common interfering species in tablets and biological samples. This study contributes to the development of nitrogen-rich porous organic polymers and offers a novel strategy for addressing challenges in disease therapeutic efficacy and public safety monitoring.


Assuntos
Indóis , Isoindóis , Isoniazida , Compostos Organometálicos , Polímeros , Humanos , Alumínio , Antituberculosos/uso terapêutico
7.
Cancer Lett ; 583: 216635, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38237887

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer (BC) with a high mortality rate, and few effective therapeutic strategies are available. CCL5/CCR5 is an appealing immunotherapeutic target for TNBC. However, its signaling mechanism is poorly understood and its direct antagonists have not been reported. Here, we developed a high-throughput screening (HTS) assay for discovering its antagonists. Verteporfin was identified as a more selective and potent antagonist than the known CCR5 antagonist maraviroc. Without photodynamic therapy, verteporfin demonstrated significant inhibition on TNBC tumor growth through immune regulation, remarkable suppression of lung metastasis by cell-intrinsic mechanism, and a significant extension of overall survival in vivo. Mechanistically, CCR5 was found to be essential for expression of the key hippo effector YAP1. It promoted YAP1 transcription via HIF-1α and exerted further control over the migration of CD8+ T, NK, and MDSC immune cells through chemokines CXCL16 and CXCL8 which were identified from RNA-seq. Moreover, the CCR5-YAP1 axis played a vital role in promoting metastasis by modulating ß-catenin and core epithelial-mesenchymal transition transcription factors ZEB1 and ZEB2. It is noteworthy that the regulatory relationship between CCR5 and YAP1 was observed across various BC subtypes, TNBC patients, and showed potential relevance in fifteen additional cancer types. Overall, this study introduced an easy-to-use HTS assay that streamlines the discovery of CCL5/CCR5 axis antagonists. Verteporfin was identified as a specific molecular probe of this axis with great potentials as a therapeutic agent for treating sixteen malignant diseases characterized by heightened CCR5 and YAP1 levels.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Verteporfina/farmacologia , Quimiocina CCL5 , Transdução de Sinais , Maraviroc/farmacologia , Linhagem Celular Tumoral , Movimento Celular , Receptores CCR5/metabolismo
8.
Nanotechnology ; 35(17)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38241719

RESUMO

Fe-doped SiGe bulk alloys are fabricated using non-equilibrium spark plasma sintering (SPS) and their structure and ferromagnetic and magneto-transport properties are investigated. X-ray diffraction and high-resolution transmission electron microscope measurements show that the obtained alloys are composed of SiGe polycrystals. Magnetization measurements reveal that the Fe-doped SiGe alloys exhibit ferromagnetism up to 259 K, and their Curie temperature increases with Fe doping concentration up to 8%. Moreover, transport measurements of the Fe-doped SiGe alloys show typical metal-insulator transition characteristics of doped semiconductors as well as anomalous Hall effect and intriguing positive-to-negative magnetoresistance, indicating that the obtained alloys are diluted magnetic semiconductors (DMSs). Our results provide insight into the SPS-prepared Fe-doped SiGe bulk alloys and may be useful for the design, fabrication, and application of group-IV DMSs.

9.
Phytochemistry ; 219: 113962, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38185394

RESUMO

Thirteen previously undescribed iridoids (1-13), together with five known iridoids (14-18) were isolated from the roots and rhizomes of Valeriana jatamansi Jones. Their structures with absolute configurations were elucidated by analysis of MS, NMR, optical rotation and their experimental and calculated electronic circular dichroism spectra. All of the isolated compounds were tested for their protective effects against α-hemolysin-induced cell death in A549 cells. Compounds 14, 16 and 17 showed moderate protective effects, and compounds 15 and 18 showed weak protective effects.


Assuntos
Nardostachys , Valeriana , Rizoma , Valeriana/química , Proteínas Hemolisinas/análise , Estrutura Molecular , Iridoides/farmacologia , Iridoides/química , Raízes de Plantas/química
10.
Fitoterapia ; 174: 105840, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38296167

RESUMO

The phytochemical investigation of the aerial parts of Isodon japonica var. glaucocalyx afforded four undescribed (glaucocalyxin O-R, 1-4) and six known ent-kauranoids (5-10). Their structures were established using NMR and MS measurements. Compounds 1 and 2 are dimeric ent-kaurane-type diterpenoids. Moreover, the plausible biogenetic pathways for compounds 1 and 2 were proposed as Michael addition between two monomers. Eight compounds were assayed for their anti-inflammatory activity by evaluating NO production in LPS-induced RAW 267.4 cells, and compounds 7, 8 and 9 exhibited relatively remarkable anti-inflammatory activities at 10 µM.


Assuntos
Antineoplásicos Fitogênicos , Diterpenos do Tipo Caurano , Diterpenos , Isodon , Isodon/química , Estrutura Molecular , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos/química , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais
11.
Int J Ophthalmol ; 17(1): 188-200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38239939

RESUMO

AIM: To summarize the application of deep learning in detecting ophthalmic disease with ultrawide-field fundus images and analyze the advantages, limitations, and possible solutions common to all tasks. METHODS: We searched three academic databases, including PubMed, Web of Science, and Ovid, with the date of August 2022. We matched and screened according to the target keywords and publication year and retrieved a total of 4358 research papers according to the keywords, of which 23 studies were retrieved on applying deep learning in diagnosing ophthalmic disease with ultrawide-field images. RESULTS: Deep learning in ultrawide-field images can detect various ophthalmic diseases and achieve great performance, including diabetic retinopathy, glaucoma, age-related macular degeneration, retinal vein occlusions, retinal detachment, and other peripheral retinal diseases. Compared to fundus images, the ultrawide-field fundus scanning laser ophthalmoscopy enables the capture of the ocular fundus up to 200° in a single exposure, which can observe more areas of the retina. CONCLUSION: The combination of ultrawide-field fundus images and artificial intelligence will achieve great performance in diagnosing multiple ophthalmic diseases in the future.

12.
Nanoscale ; 16(2): 527-554, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38063022

RESUMO

Owing to their atomic thicknesses, atomically flat surfaces, long-range spin textures and captivating physical properties, two-dimensional (2D) magnetic materials, along with their van der Waals heterostructures (vdWHs), have attracted much interest for the development of next-generation spin-based materials and devices. As an emergent family of intrinsic ferromagnetic materials, Fe3X(X=Ge and Ga)Te2 has become a rising star in the fields of condensed matter physics and materials science owing to their high Curie temperature and large perpendicular magnetic anisotropy. Herein, we aim to comprehensively summarize the recent progress on 2D Fe3X(X=Ge and Ga)Te2 and their vdWHs and provide a panorama of their physical properties and underlying mechanisms. First, an overview of Fe3X(X=Ge and Ga)Te2 is presented in terms of crystalline and electronic structures, distinctive physical properties and preparation methods. Subsequently, the engineering of electronic and spintronic properties of Fe3X(X=Ge and Ga)Te2 by diverse means, including strain, gate voltage, substrate and patterning, is surveyed. Then, the latest advances in spintronic devices based on 2D Fe3X(X=Ge and Ga)Te2 vdWHs are discussed and elucidated in detail, including vdWH devices that exploit the exchange bias effect, magnetoresistance effect, spin-orbit torque effect, magnetic proximity effect and Dzyaloshinskii-Moriya interaction. Finally, the future outlook is given in terms of efficient large-scale fabrication, intriguing physics and important technological applications of 2D Fe3X(X=Ge and Ga)Te2 and their vdWHs. Overall, this study provides an overview to support further studies of emergent 2D Fe3X(X=Ge and Ga)Te2 materials and related vdWH devices for basic science and practical applications.

13.
Fitoterapia ; 173: 105786, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38135093

RESUMO

Four kinds of tea polysaccharides (MBTPS, MGTPS, ZBTPS, ZGTPS) were extracted from Maofeng black tea, Maofeng green tea,Ziyan black tea and Ziyan green tea, and then four tea polysaccharides (RMBTPS, RMGTPS, RZBTPS, RZGTPS) after metal removal were prepared. The physicochemical properties, antioxidant activity and inhibitory activity on cancer cell proliferation of the above polysaccharides were studied. The composition analysis shows that these tea polysaccharides were glycoproteins complexes, composed of a variety of monosaccharides, and the removal of metal ions did not lead to fundamental changes in the composition of polysaccharides. In vitro activity, after removing metal ions, the ABTS free radicals scavenging ability and reducing power of tea polysaccharides were decreased, and the inhibitory effect on proliferation of H22 cells weakened. There was a great correlation between metal elements Al and Ni and biological activity. The results showed that the metal ions in tea polysaccharides, especially Al and Ni, had positive effects on biological activity.


Assuntos
Antioxidantes , Neoplasias , Antioxidantes/farmacologia , Antioxidantes/química , Estrutura Molecular , Polissacarídeos/farmacologia , Polissacarídeos/química , Chá/química , Metais/química , Íons
14.
Nanoscale ; 16(3): 1345-1351, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38131394

RESUMO

5d transition-metal compounds are usually not expected to exhibit distinct magnetic ordering owing to their substantial binding energy associated with 5d electrons. In this study, we demonstrate that two-dimensional (2D) 5d transition-metal Os trihalide OsX3 monolayers can exhibit room-temperature ferromagnetism and quantum anomalous Hall effect (QAHE) by utilizing density functional theory and Monte Carlo simulation. Our calculation results of coexisting Raman and infrared activities of lattice vibration reveal the structural stability of 2D OsX3 (X = Cl, Br, I) and structural instability of 2D OsX3 (X = F). Furthermore, all 2D OsX3 trihalides (X = Cl, Br, I) are half-metals, and their ferromagnetism remains stable under ambient temperature, where 2D OsCl3 and OsBr3 have an in-plane easy axis while 2D OsI3 has an out-of-plane easy axis. Notably, when spin-orbit coupling is included, the gate-tunable QAHE could emerge in ferromagnetic 2D OsI3, while 2D OsCl3 and OsBr3 are topologically trivial. Additionally, the magnon bands of 2D OsX3 (X = Cl, Br, I) possess two spin-wave branches with dispersion similar to that of the Dirac cone in the electronic structure of graphene, which are attributed to the unique ferromagnetic honeycomb sublattice of osmium atoms.

15.
Front Endocrinol (Lausanne) ; 14: 1195966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047115

RESUMO

Objective: We aimed to explore the association between serum complements and kidney function of diabetic kidney disease (DKD) in Chinese patients. Methods: This is a retrospective study involving 2,441 participants. DKD was diagnosed according to the Kidney Disease: Improving Global Outcomes (KDIGO) categories. Participants were classified as stages G1-G5 by KDIGO glomerular filtration rate (GFR) categories. Effect sizes are expressed as odds ratio (OR) with 95% confidence interval (CI). Results: After balancing age, gender, systolic blood pressure (SBP), hemoglobin A1c (HbA1C), serum triglyceride (TG), and urinary albumin-to-creatinine ratio (UACR) between the G2-G5 and control groups, per 0.1 g/L increment in serum complement C3 was significantly associated with a 27.8% reduced risk of DKD at G5 stage (OR, 95% CI, P: 0.722, 0.616-0.847, <0.001) relative to the G1 stage. Conversely, per 0.1 g/L increment in serum complement C4 was associated with an 83.0-177.6% increased risk of G2-G5 stage (P<0.001). Serum complement C1q was not statistically significant compared to controls at all stages prior to or after propensity score matching. Conclusions: Our results indicate that high concentrations of serum C4 were associated with the significantly elevated risk of kidney function deterioration across all stages, and reduced serum C3 levels with an increased risk of DKD stage G5.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/diagnóstico , Estudos Retrospectivos , Rim , Testes de Função Renal , Taxa de Filtração Glomerular/fisiologia
16.
J Diabetes Res ; 2023: 8848096, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094871

RESUMO

Objectives: Type 2 diabetic kidney disease (DKD), a chronic microvascular complication of diabetes, may exhibit a complex interrelation with coagulation function. This study is aimed at elucidating the association between coagulation function and DKD. Methods: This was a real-world observational study conducted in Beijing, involving 2,703 participants. All patients with diabetes were classified into two groups, viz., DKD and non-DKD groups. Effect magnitudes are denoted as odds ratios (OR) with a 95% confidence interval (CI). To mitigate potential bias in group comparisons, we employed propensity score matching (PSM). Results: After adjusting for variables such as age, gender, systolic blood pressure (SBP), hemoglobin A1c (HbA1c), triglyceride (TG), c-reactive protein (CRP), platelet (PLT), and serum albumin (sALB), it was discerned that fibrinogen (FIB) (OR, 95% CI, P: 1.565, 1.289-1.901, <0.001) and fibrinogen degradation products (FDP) (1.203, 1.077-1.344, 0.001) were significantly correlated with an increased risk of DKD. To facilitate clinical applications, a nomogram prediction model was established, demonstrating commendable accuracy for DKD prediction. Conclusions: Our findings suggest that elevated levels of FIB and FDP serve as potential risk indicators for DKD, and coagulation function may play an important role in the occurrence and development of DKD.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/metabolismo , Diabetes Mellitus Tipo 2/complicações , Fatores de Risco , Proteína C-Reativa , Fibrinogênio
17.
Analyst ; 148(24): 6274-6281, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37969078

RESUMO

Vanillin (Van) is widely utilized in processed foods and medicines for its appealing scent and multiple therapeutic benefits. However, its overconsumption poses a risk to public health, making its quantification essential for ensuring food and medicine safety and quality. This study introduces a stable and conductive phthalocyanine-based porous organic polymer (NiPc-CC POP), synthesized through a straightforward electrophilic substitution of nickel tetra-amine phthalocyanine (NiTAPc) with cyanuric chloride (CC). Appropriate characterization techniques were employed to determine the morphologies and structures of the synthesized materials. Furthermore, the NiPc-CC POP was applied to devise a sensitive Van detection method. Leveraging the high electrocatalytic activity of NiPc-CC POP toward Van oxidation, a linear response of 0.15-32 µmol L-1 was achieved, along with an exceptional detection limit of 0.10 µmol L-1. The sensor demonstrated high selectivity and stability. Samples of human serum and tablets spiked with Van were analyzed, yielding satisfactory recoveries. Consequently, this work contributes to the advancement of sensitive detection platforms for Van at minimal concentrations.


Assuntos
Isoindóis , Polímeros , Humanos , Porosidade
18.
ACS Appl Mater Interfaces ; 15(48): 56049-56056, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38009363

RESUMO

Owing to its high stability, suitable absorption band gap, and fast response time, MoSe2 has attracted the most attention in transition-metal dichalcogenides (TMDCs) for photodetector (PD) applications. In this study, based on centimeter-scale smooth amorphous MoSe2 (a-MoSe2) thin films with thicknesses varying from 6.5 to 62.5 nm on a-SiO2/Si substrates prepared by polymer-assisted deposition, metal-semiconductor-metal-structured self-powered a-MoSe2 PDs are designed and fabricated. Our data show that the PD based on 9.5 nm thick a-MoSe2 thin film exhibits the highest values of photocurrent (Iph, 4.60 µA), photo-to-dark current ratio (PDCR, 3067), photoresponsivity (Rλ, 0.94 mA/W), and detectivity (D*, 4.29 × 1010 Jones), as well as the lowest values of noise-equivalent power (NEP, 2.33 × 10-11 W/Hz1/2) and photoresponse rise/decay time (61/58 ms) under a 405 nm laser with 5 mW power at zero bias, which are better than or comparable with those of previously reported PDs based on crystalline MoSe2 monolayers or other atomically thin 2D materials under bias voltage. The high-performance mechanism can be explained in terms of the energy band theory and volume modulation photoconductive gain model in a-MoSe2 with a spontaneous built-in electric field. Our work provides a scalable low-cost way for the design and fabrication of high-performance self-powered TMDC PDs.

19.
JOR Spine ; 6(3): e1256, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37780830

RESUMO

Background: Adolescent idiopathic scoliosis (AIS) is a scoliotic deformity of unknown etiology that occurs during adolescent development. Abnormal bone metabolism is closely related to AIS, but the cause is uncertain. Recent studies have shown that heat shock protein 27 (HSP27) and its phosphorylation (pHSP27) play important roles in bone metabolism. However, whether HSP27 and pHSP27 are involved in abnormal bone metabolism in AIS is unclear. Methods: Osteoblasts (OBs) and bone marrow stem cells (BMSCs) were extracted from the facet joints and bone marrow of AIS patients and controls who underwent posterior spinal fusion surgery. The expression levels of HSP27 and pHSP27, as well as the expression levels of bone formation markers in OBs from AIS patients and controls, were examined by quantitative real-time PCR (qRT-PCR) and Western blotting. The mineralization ability of OBs from AIS patients and controls was analyzed by alizarin red staining after osteogenic differentiation. Heat shock and thiolutin were used to increase the levels of pHSP27 in OBs, and the levels of bone formation markers were also investigated. In addition, the levels of pHSP27 and the bone formation ability of BMSCs from AIS patients and controls were investigated after heat shock treatment. Results: Lower pHSP27 levels and impaired osteogenic differentiation abilities were observed in the OBs of AIS patients than in those of controls. Thiolutin increased HSP27 phosphorylation and increased the mRNA levels of SPP1 and ALPL in OBs from AIS patients. Heat shock treatment increased SPP1 and HSP27 mRNA expression, pHSP27 levels, OCN expression, and mineralization ability of both OBs and BMSCs from AIS patients. Conclusion: Heat shock treatment and thiolutin can increase the levels of pHSP27 and further promote the bone formation of OBs and BMSCs from AIS patients. Therefore, decreased pHSP27 levels may be associated with abnormal bone metabolism in AIS patients.

20.
Artigo em Inglês | MEDLINE | ID: mdl-37906719

RESUMO

Electrospun nanofiber (NF)-based triboelectric nanogenerators (TENGs) have attracted significant attention in recent years due to their high specific surface area, flexibility, and facile fabrication. However, these TENGs' triboelectric (TE) layers composed of electrospun NFs fail easily due to the poor mechanical properties and fluffy characteristics of the NFs. Herein, electropositive and electronegative TE layers based on ethylcellulose-coated nylon-11 (EC/nylon-11) NFs and polytetrafluoroethylene-coated poly(vinylidene fluoride) (PTFE/PVDF) NFs are prepared via electrospinning and postcoating processes. The obtained EC/nylon-11 and PTFE/PVDF NFs are fluffy-free and exhibit 12.26 and 20.33-fold enhancements of Young's modulus compared with those of pure nylon-11 and PVDF NFs, respectively. The optimized TENG exhibits not only superior performance, including an open-circuit voltage (VOC) of 212 V, a short-circuit current (ISC) of 18.5 µA, and a maximum power density of 1.76 W/m2 but also excellent electrical durability for over 100,000 cycles. The TENG's capability is further demonstrated by continuously driving electronics for over 5 min and by being integrated into a self-powered sensor array of electric skin to detect different in vitro stimuli. This work provides an effective approach to obtaining mechanically robust and electrically stable NF-based high-performance TENGs, which may have potential applications in durable, wearable, and self-powered nanoelectronics.

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