Orthopaedic Surgery
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2022
·Vol. 14
·期 10
·2669-2681
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IF 2.279
Bo-yong Jang,Shi-bing Guo,Rui Bai,Wan-lin Liu,Yu-lin Gong,Zhen-qun Zhao
Objective To study the relationship between vascular endothelial cells (VEC) and autophagy, and its regulatory mechanism in steroid-induced avascular necrosis of the femoral head (SANFH). Methods In cell experiment, VEC were isolated and cultured from the femoral head of Sprague–Dawley rats and divided into three groups: blank control group (Ctrl), methylprednisolone group (MP), and methylprednisolone+mTOR-shRNA group (MP + shmTOR). The autophagy formation was observed by transmission electron microscope. The mRNA expression of PI3K, Akt, mTOR, Beclin1 and MAP1LC3 was detected by RT-PCR and the protein expression was detected by Western blot and immunofluorescence. Expression of the damage marker 6-keto-PGF1α was detected by the ELISA method. In vivo experiment, after establishing the model, the grouping method was the same as cell experiment. Autophagosomes were observed by same method, and the expression of related factors was detected by the same method in cell experiment. Results In the cell experiment, autophagosomes in the MP group were significantly lower than in the Ctrl group, and the autophagosomes in the MP + shmTOR group were intermediate between two groups ( P < 0.05). The mRNA expression levels of PI3K, Akt and mTOR in the MP group were significantly higher than in the Ctrl group, while the MP+ shmTOR group presented intermediate levels between these groups (average gray value were 3837.90, 2996.30, 3005.60, F = 428.64, P < 0.05). MRNA expression levels of Beclin1 and MAP1LC3 in the MP group were significantly lower than that in Ctrl group ( P < 0.05). The content of 6-keto-PGF1α in the MP + shmTOR group was higher than in the Ctrl group and lower than in the MP group at the evaluated time intervals (average absorbance value were 104.98, 206.83, 145.91, F = 352.83, P < 0.01). In vivo experiment, the content of 6-Keto-PGF1α in the hormone group increased as time went on; the mTOR-si group was higher than that in control group, but lower than that in the hormone group ( P < 0.01). The mRNA expressions of Beclin1 and MAP1LC3 in the control group were higher than those in the hormone group, while the mRNA expressions of PI3K, Akt and mTOR were lower than those in the mTOR-si group ( P < 0.05). Conclusion The steroid inhibited the physiological protective effect of autophagy on SANFH by increasing the expression of PI3K/Akt/mTOR signaling pathway related factors and decreasing the expression of Beclin1 and MAP1LC3 in the femoral head VEC.
研究领域:
药理学
·
细胞生物学
·
骨科
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DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
IF 4.551
Shushu Huang,Dengyao Yang,Qianxi Tang,Wei Deng,Long Zhang,Ziye Jia,Zhengfang Tian,Qiang Gao,Limin Guo
In this study, the Pt-loaded ellipsoidal nanozeolite (Pt/ZSM-5-OS) was successfully synthesized by the mercaptosilane modification assisted Pt dispersion method and investigated for the catalytic combustion of toluene, which was used as a model compound of volatile organic compounds (VOCs). The catalytic activity evaluation showed that Pt/ZSM-5-OS exhibited an excellent activity in toluene catalytic combustion, with 90% conversion (T 90 ) occurring at just 164 °C. The catalytic activity was much higher than the catalyst prepared by traditional impregnation method (Pt/ZSM-5-IM, T 90 = 196 °C). In addition, the excellent properties of anti-water vapor and catalytic stability were observed for Pt/ZEM-5-OS. The as-prepared catalysts were characterized by X-ray diffraction (XRD), N 2 physisorption , scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Characterization of the as-prepared catalysts demonstrated that the enhanced catalytic performance was related to the improved Pt dispersion and higher Pt 0 proportion of Pt-ZSM-5-OS. Hence, Pt/ZSM-5-OS and its preparation method are attractive for the practical VOCs catalytic combustion.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-10
·
IF 17.694
Li Yinghao,Peng Chun-Kuo,Hu Huimin,Chen San-Yuan,Choi Jin-Ho,Lin Yan-Gu,Lee Jong-Min
Developing high-performance electrocatalysts for hydrogen evolution reaction (HER) is crucial for sustainable hydrogen production, yet still challenging. Here, we report boron-modulated osmium (B-Os) aerogels with rich defects and ultra-fine diameter as a pH-universal HER electrocatalyst. The catalyst shows the small overpotentials of 12, 19, and 33 mV at a current density of 10 mA cm −2 in acidic, alkaline, and neutral electrolytes, respectively, as well as excellent stability, surpassing commercial Pt/C. Operando X-ray absorption spectroscopy shows that interventional interstitial B atoms can optimize the electron structure of B-Os aerogels and stabilize Os as active sites in an electron-deficient state under realistic working conditions, and simultaneously reveals the HER catalytic mechanisms of B-Os aerogels in pH-universal electrolytes. The density functional theory calculations also indicate introducing B atoms can tailor the electronic structure of Os, resulting in the reduced water dissociation energy and the improved adsorption/desorption behavior of hydrogen, which synergistically accelerate HER.
研究领域:
材料科学
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电化学
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催化
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可持续能源
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DOI
PubMed
高影响因子
BIOLOGICAL & PHARMACEUTICAL BULLETIN
·
2022
·Vol. 45
·期 12
·1733-1742
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IF 2.264
Yongbin Jing,Mingkun Jia,Jinpeng Zhuang,Dong Han,Changlong Zhou,Jinglong Yan
Osteosarcoma (OS) is the most common primary malignant bone tumor and is mainly diagnosed in children. Toll-like receptor 9 (TLR9) is expressed in various tumor cells and was correlated with cancer progression. However, the underlying mechanism of TLR9 on the OS progression remains unclear. Our previous study demonstrated that the expression of TLR9 was positively correlated with the development stage of OS. Herein, we further evaluated the actual roles and the molecular mechanism of TLR9 on regulating OS cell proliferation and metastasis. Our data showed that TLR9 was upregulated in OS cells compared to normal osteoblastic cells, and knockdown of TLR9 inhibited OS cell proliferation and induced cell cycle arrest by the decreased expression of cyclin D1, CDK2, and p-Rb, while TLR9 overexpression exerted the inverse effects. Furthermore, TLR9 overexpression could enhance the migration and invasion activities of the OS cells by the upregulation of matrix metalloproteinases 2 (MMP2) and MMP9, and the opposite result was observed in TLR9-silenced cells. Moreover, the nuclear factor kappa B (NF-κB) signaling pathway was activated by TLR9, and TLR9-induced malignant phenotype of OS cells was abrogated by the NF-κB antagonist BAY11-7082. Our study indicated that TLR9 might play a critical role in facilitating OS progression by activating the NF-κB signaling pathway, which may provide a valuable therapeutic target for OS.
研究领域:
肿瘤学
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细胞生物学
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分子生物学
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癌症研究
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DOI
PubMed
高影响因子
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
·
2025
·Vol. 38
·期 7
·075014
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IF 4.2
Manikandan Krishnan,Jiaojiao Meng,Bai-zhuo Li,Yanmei Ma,Cao Wang,Dilip Bhoi,Yoshiya Uwatoko,Qiang Jing,Bo Liu
Structural, superconducting ground state, and normal state properties on Re-Os-W-Mo-Ta high-entropy alloys (HEAs) were investigated using powder x-ray diffraction, magnetization measurements, electrical resistivity analysis, and specific heat measurements. The structural phase transformation was found to develop through compositional variations of the primary elements of HEAs, leading to the formation of phases such as bcc-type Re23Os5W33Mo34Ta5, σ-type Re31Os18W23Mo23Ta5, and α-Mn-type Re33Os34W11Mo11Ta11. These impurity-free samples, displaying a single-phase structure, exhibit bulk superconducting behavior. Low-temperature specific heat analysis indicates that the bcc-type and σ-type HEAs exhibit weakly coupled, whereas the α-Mn-type HEA exhibits strongly coupled, isotropic and fully gapped superconductivity. Moreover, the stability of bcc-type, σ-type, and α-Mn-type HEAs is significantly influenced by key factors such as valence electron count and electronegativity differences. This study presents observations of structural transformations in HEAs driven by compositional variations without the introduction of additional elements, providing significant insights into the correlation between structural changes and superconducting properties in highly disordered systems.
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高影响因子
RSC Advances
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2024
·Vol. 14
·期 14
·9996-10003
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IF 3.9
Zijie Wei,Cuifeng Jiang,Jinshan Wang,Yue Chen
Metal organic framework (MOF)-derived nanostructures display remarkable characteristics and have broad application potential. Os@ZIF-8 nanocomposites were prepared by a depositional method. The Os nanoparticles distributed on the surface of ZIF-8. The nanocomposites displayed enhanced peroxidase-like activity with smaller Km for both 3,3′,5,5′-tetramethylbenzidine (TMB) and H2O2 compared to Os NPs due to the confinement effect and large surface area that ZIF-8 provided. From the average reaction rate constants obtained from three different temperatures, the activation energy values were determined. The kinetic data indicated that the Os@ZIF-8 NCs are catalytically more active than Os NPs. In addition, quantitative measurement of Hg2+ was performed based on the formation of Os–Hg alloy. Os@ZIF-8 NCs had a wide detection range between 0 μM and 71.43 μM for Hg2+ with a limit of detection (LOD) of 2.29 μM. Using a MOF with a large surface area to load Os nanoparticles to achieve enhanced nanozyme activity is the novelty of this work.
研究领域:
材料科学
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生物化学
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PubMed
高影响因子
MICROCHIMICA ACTA
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2024
·Vol. 191
·期 8
·1-10
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IF 5.3
Lin Feng-Lin,Guo Xiao-Yun,Shen Huan-Ran,Guo Xiu-Mei,Dai Yun,Zheng Qiong-Hua,Chen Jin-Cheng,Xu Qiu-Xia,Zhang Yin,He Shao-Bin,Chen Wei
Hydroxyl radical ( · OH) scavenging capacity (HOSC) estimation is essential for evaluating antioxidants, natural extracts, or drugs against clinical diseases. While nanozymes offer advantages in related applications, they still face limitations in activity and selectivity. In response, this work showcases the fabrication of laminarin-modulated osmium (laminarin-Os) nanoclusters (1.45 ± 0.05 nm), functioning as peroxidase-like nanozymes within a colorimetric assay tailored for rational HOSC estimation. This study validates both the characterization and remarkable stability of laminarin-Os. By leveraging the abundant surface negative charges of laminarin-Os and the surface hydroxyls of laminarin, oxidation reactions are facilitated, augmenting laminarin-Os’s affinity for 3,3′,5,5′-tetramethylbenzidine (TMB) ( K M = 0.04 mM). This enables the laminarin-Os-based colorimetric assay to respond to · OH more effectively than citrate-, albumin-, or other polysaccharides-based Os. In addition, experimental results also validate the selective peroxidase-like behavior of laminarin-Os under acidic conditions. Antioxidants like ascorbic acid, glutathione, tannic acid, and cysteine inhibit absorbance at 652 nm in the colorimetric platform using laminarin-Os’s peroxidase-like activity. Compared with commercial kits, this assay demonstrates superior sensitivity (e.g., responds to ascorbic acid 0.01–0.075 mM, glutathione 1–15 µg/mL, tannic acid 0.5–5 µM, and monoammonium glycyrrhizinate cysteine 1.06–10.63 µM) and HOSC testing for glutathione, tannic acid, and monoammonium glycyrrhizinate cysteine. Overall, this study introduces a novel Os nanozyme with exceptional TMB affinity and · OH selectivity, paving the way for HOSC estimation in biomedical research, pharmaceutical analysis, drug quality control, and beyond. Graphical abstract
研究领域:
生物医学
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药物分析
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纳米技术
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DOI
PubMed
高影响因子
Materials Today Bio
·
2024
·
IF 8.7
Lin Ye,Congcong Yu,Jiechao Xia,Kainan Ni,Yejin Zhang,Xiaozhang Ying,Dingqi Xie,Yang Jin,Rongtai Sun,Ruikang Tang,Shunwu Fan,Shasha Yao
Reactive Oxygen Species (ROS) refers to a highly reactive class of oxidizing species that have the potential to induce cellular apoptosis and necrosis. Cuproptosis, a type of cell death, is primarily associated with the effects of copper ions. However, the specific relationship between ROS, cuproptosis, and osteosarcoma (OS) remains relatively unexplored. Additionally, there is limited research on the use of cuproptosis in conjunction with oxidative stress for treating OS and inhibiting tumor-induced bone destruction. To address these gaps, a novel treatment approach has been developed for OS and neoplastic bone destruction. This approach involves the utilization of glutathione (GSH) and pH-responsive organic-inorganic mesoporous silica nanoparticles@Cu 2 S@oxidized Dextran (short for MCD). The MCD material demonstrates excellent cytocompatibility, osteogenesis, tumor suppression, and the ability to inhibit osteoclast formation. The specific mechanism of action involves the mitochondria of the MCD material inhibiting key proteins in the tricarboxylic acid (TCA) cycle. Simultaneously, the generation of ROS promotes this inhibition and leads to alterations in cellular energy metabolism. Moreover, the MCD biomaterial exhibits promising mild-temperature photothermal therapy in the second near-infrared (NIR-II) range, effectively mitigating tumor growth and OS-induced bone destruction in vivo .
研究领域:
肿瘤学
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生物医学工程
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药理学
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DOI
PubMed
高影响因子
Russian Journal of Physical Chemistry A
·
2022
·Vol. 96
·期 7
·1561-1566
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IF 0.791
Xu Rong,Tan Hao,Guo Meng,Zuo Shixiang,Sun Xueni
Abstract Thiol-functionalized organosilica (OS-SH) was synthesized via an ultra-fast sol–gel procedure without using any templates. The OS-SH was then employed as an adsorbent to remove Hg(II) ions from aqueous solution. Pore structure and material morphology were characterized by FTIR, TGA, SEM, TEM, and N 2 sorption measurements. The OS-SH adsorbents demonstrated an outstanding adsorption performance (72.48 mg g –1 at pH 3). The adsorption isotherm can be best described by the Langmuir model, suggesting a monolayer adsorption behavior by chemical mechanism. The adsorption kinetics of Hg(II) on OS‑SH was well fitted by the pseudo-second-order model. The synthesis approach proposed in this study provides a much simple, tender as well as highly efficient way to design functional porous adsorbents for the removal of heavy metal ions.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Yunfei Li,Pengcheng Zhao,Jiabao Huang,Luocai Yi,Chengsi Hu,Ying Li,Liu Yang,Qingjun Chen
A single-atom alloy with isolated Os in NiCu was constructed. • Os promotes water dissociation on Ni sites and optimizes hydrogen binding. • Reconfiguration of interfacial water yields a free-water-rich environment. • The catalyst delivers excellent performance and durability in an AEMWE device. Developing efficient and durable alkaline hydrogen evolution reaction (HER) catalysts is essential for sustainable hydrogen production via anion-exchange membrane water electrolysis (AEMWE) yet remains challenging. Herein, we report a single-atom alloy catalyst comprising atomically dispersed Os on the NiCu alloy array support (Os SA/NiCu), where the unique coordination environment engenders strong electronic interactions that synergistically enhance catalytic activity. The optimized catalyst achieves an overpotential of only 14 mV at 10 mA cm −2 and operates stably for over 2000 h at 200 mA cm −2 . Combined in situ spectroscopy and theoretical calculations reveal that the Os incorporation facilitates water dissociation on adjacent Ni sites, optimizes hydrogen binding energetics, and reconstructs the local interfacial water structure, thereby accelerating alkaline HER kinetics. When employed as the cathode in an AEMWE device, Os SA/NiCu delivers a cell voltage of 1.76 V at an industrial-relevant current density of 1 A cm −2 at 80 °C, with exceptional stability exceeding 500 h. This work establishes single-atom alloy engineering as an effective strategy to enhance noble metal utilization and intrinsic activity toward durable AEMWE systems. A single-atom alloy catalyst comprising atomically dispersed Os on a NiCu alloy array support was synthesized. In situ spectroscopy and DFT reveal that Os incorporation accelerates alkaline HER by synergistically modulating water dissociation, hydrogen binding, and interfacial water structure. Consequently, the catalyst achieves 1 A cm −2 at 1.76 V and operates stably at 0.5 A cm −2 for 1000 h in an AEMWE device. Download: Download high-res image (127KB) Download: Download full-size image
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DOI
高影响因子
MOLECULAR NEUROBIOLOGY
·
2024
·
IF 4.6
Wang Zhenhua,Li Yuan,Wang Zhixu,Liao Yuhui,Ye Qingqing,Tang Shilong,Wei Ting,Xiao Pengyu,Huang Juan,Lu Weitian
Oxidative stress (OS) is the main cause of secondary damage following intracerebral hemorrhage (ICH). The polarity expression of aquaporin-4 (AQP4) has been shown to be important in maintaining the homeostasis of water transport and preventing post-injury brain edema in various neurological disorders. This study primarily aimed to investigate the effect of the oxygen free radical scavenger, edaravone, on AQP4 polarity expression in an ICH mouse model and determine whether it involves in AQP4 polarity expression via the OS/MMP9/β-dystroglycan (β-DG) pathway. The ICH mouse model was established by autologous blood injection into the basal nucleus. Edaravone or the specific inhibitor of matrix metalloproteinase 9 (MMP9), MMP9-IN-1, called MMP9-inh was administered 10 min after ICH via intraperitoneal injection. ELISA detection, neurobehavioral tests, dihydroethidium staining (DHE staining), intracisternal tracer infusion, hematoxylin and eosin (HE) staining, immunofluorescence staining, western blotting, Evans blue (EB) permeability assay, and brain water content test were performed. The results showed that OS was exacerbated, AQP4 polarity was lost, drainage function of brain fluids was damaged, brain injury was aggravated, expression of AQP4, MMP9, and GFAP increased, while the expression of β-DG decreased after ICH. Edaravone reduced OS, restored brain drainage function, reduced brain injury, and downregulated the expression of AQP4, MMP9. Both edaravone and MMP9-inh alleviated brain edema, maintained blood–brain barrier (BBB) integrity, mitigated the loss of AQP4 polarity, downregulated GFAP expression, and upregulated β-DG expression. The current study suggests that edaravone can maintain AQP4 polarity expression by inhibiting the OS /MMP9/β-DG pathway after ICH.
研究领域:
神经科学
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药理学
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病理生理学
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PubMed
高影响因子
DALTON TRANSACTIONS
·
2019
·Vol. 48
·期 31
·11763-11771
·
IF 4.052
Yaxiong Wei,Min Zheng,Lin Chen,Xiaoguo Zhou,Shilin Liu
Three Os(II) complexes were synthesized with ligands 2,2′-dipyridyl (dipy), 1,10-phenanthroline monohydrate (phen), and 4,7-diphenyl-1,10-phenanthroline (diphen), and applied as triplet photosensitizers for triplet–triplet annihilation (TTA) fluorescence upconversion. The strong spin-orbital coupling made direct spin-forbidden transition of S0–T1 feasible. Lifetimes of the lowest triplet state of these complexes were determined to be 107 ns, 373 ns, and 386 ns for Os-dipy, Os-phen, and Os-diphen, respectively, using nanosecond transient absorption spectra. From steady-state phosphorescence emission spectra, energies of the triplet states were derived to be 1.75 eV, 1.80 eV, and 1.74 eV for Os-dipy, Os-phen, and Os-diphen, respectively. Using these photosensitizers, strong upconverted fluorescence of the triplet acceptors, 9,10-diphenylanthracene (DPA), perylene, and 9,10-bis(phenethynyl) anthracene (BPEA), was observed in the visible to violet range. In particular, fluorescence emission with the largest anti-Stokes shift of 1.14 eV was observed for the Os-phen/DPA system, and the upconverted quantum yield was determined as 5.9% in deoxygenated dichloroethane. Additionally, upconversion was determined in air using mixtures of dichloroethane and DMSO solvents, and the maximal quantum yield was measured to be 4.5% for Os-phen/DPA.
研究领域:
化学
·
材料科学
·
光物理学
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DOI
PubMed
高影响因子
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