Publications by authors named "Zhaofei Zhang"

Axially chiral molecular scaffolds are widely found in pharmaceutical molecules, functionalized materials, and chiral ligands. The synthesis of these compounds has garnered considerable interest from both academia and industry. The construction of such molecules, enabled by transition metal catalysis and organocatalysis under thermodynamic conditions, has been extensively studied and well-reviewed.

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N-heterocyclic carbene catalysis has been developed as a versatile method for the enantioselective synthesis of complex organic molecules in organic chemistry. Merging of N-heterocyclic carbene catalysis with transition metal catalysis holds the potential to achieve unprecedented transformations with broad substrate scope and excellent stereoselectivity, which are unfeasible with individual catalyst. Thus, this dual catalysis has attracted increasing attention, and numerous elegant dual catalytic systems have been established.

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Spirocyclic compounds are abundant in biologically active products. However, the divergent synthesis of spirocyclic compounds using low-cost and abundant available starting materials remains a challenge. Herein, we report an effective method for producing spirocyclic motifs using a cyclic β-carbonyl ester or amide and ethylene via thianthrenation.

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In order to efficiently select the optimal cutting position of x-ray mono-capillary lenses, an improved sine cosine algorithm-crow search algorithm (SCA-CSA) algorithm is proposed, which combines the sine cosine algorithm with the crow search algorithm, with further enhancements. The fabricated capillary profile is measured using an optical profiler; then the surface figure error for interest regions of the mono-capillary can be evaluated using the improved SCA-CSA algorithm. The experimental results indicate that the surface figure error in the final capillary cut region is about 0.

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A merger of copper catalysis and semiconductor photocatalysis using polymeric carbon nitride (PCN) for multi-type cross-coupling reactions was developed. This dual-catalytic system enables mild C-H arylation, chalcogenation, and C-N cross-coupling reactions under visible light irradiation with a broad substrate scope. Good-to-excellent yields were obtained with appreciable site selectivity and functional group tolerance.

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Background: Icariin (ICA) can promote the migration and bone formation of bone marrow mesenchymal stem cells. This study explored a potential role of ICA in recruiting stem cell niches (SCNs) within the intervertebral disc region (ISN)-derived stem cells (ISN-SCs) to treat intervertebral disc degeneration (IVDD).

Materials And Methods: EdU staining, transwell, and wound healing tests were used to analyze the function of ICA on ISN-SCs proliferation and migration ability.

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Industrial production processes, especially petroleum processing, will produce high concentration phenolic wastewater. Traditional wastewater treatment technology is costly and may lead to secondary pollution. In order to avoid the adverse effects of incompletely treated phenolics, more advanced methods are required.

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Tandem water electrolysis for the transformation of universal feedstock to value-added chemicals integrated with hydrogen generation and in situ utilization is a promising approach to address the economic challenges of electrochemical hydrogen evolution and storage. Herein, we present the controllable electrocatalytic deuteration of halides using inexpensive and reusable heavy water (DO) as a D-source for the preparation of valuable D-labelled chemicals and pharmaceuticals under mild conditions. This electrochemical deuteration method with high efficiency and selectivity furnishes a series of D-labelled chemicals and pharmaceuticals in high yields with excellent D-incorporation.

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Hierarchical porous composite Mg-MOF-74/MCFs were successfully synthesized using a simple and facile method under solvothermal conditions. Textural structures and morphologies of the composites were characterized by X-ray diffraction (XRD), N adsorption-desorption isotherms, and scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The results demonstrate that a large amount of nanosized Mg-MOF-74 particles is incorporated into the pores of mesocellular siliceous foams (MCFs) without remarkable aggregation and the composites possess microporous and mesoporous characteristics of both components.

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Photocatalytic water splitting technology (PWST) enables the direct use of water as appealing "liquid hydrogen source" for transfer hydrogenation reactions. Currently, the development of PWST-based transfer hydrogenations is still in an embryonic stage. Previous reports generally centered on the rational utilization of the in situ generated H-source (electrons) for hydrogenations, in which photogenerated holes were quenched by sacrificial reagents.

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Precisely controlled deuterium labeling at specific sites of N-alkyl drugs is crucial in drug-development as over 50% of the top-selling drugs contain N-alkyl groups, in which it is very challenging to selectively replace protons with deuterium atoms. With the goal of achieving controllable isotope-labeling in N-alkylated amines, we herein rationally design photocatalytic water-splitting to furnish [H] or [D] and isotope alkanol-oxidation by photoexcited electron-hole pairs on a polymeric semiconductor. The controlled installation of N-CH -CDH -CDH, -CD, and -CH groups into pharmaceutical amines thus has been demonstrated by tuning isotopic water and methanol.

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Objective: This study evaluated the biomechanical changes in the adjacent vertebrae under a physiological load (500 N) when the clinically relevant amount of bone cement was injected into fractured cadaver vertebral bodies.

Methods: The embalmed cadaver thoracolumbar specimens in which each vertebral body (T12-L2) had a BMD of < 0.75 g/cm were used for the experiment.

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Objective: To evaluate the analgesic effect of vertebral cancellous bone infiltration anaesthesia during percutaneous vertebroplasty (PVP).

Methods: Patients treated with vertebral cancellous bone infiltration anaesthesia (intervention group) or local anaesthesia alone (control group) during PVP at our institution during 2016-2018 were reviewed. The visual analogue scale (VAS) score before the operation, during establishment of the puncture channel, during pressure changes in the vertebral body (e.

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Stem cell therapy is widely employed in treating osteoarthritis (OA), and bone marrow-derived mesenchymal stem cells (BMSCs) has gradually become the most attractive new method for treating OA due to the benefit for cartilage tissue repair. However, the apoptosis in the neural stem cell transplantation severely decreases repairing efficacy. Icariin has been reported to exert multiple effects on BMSCs, including its proliferation, osteogenic, and chondrogenic differentiation.

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Study Design: Retrospective cohort study.

Objective: To evaluate the effect of time to first ambulation on recurrence after percutaneous endoscopic lumbar discectomy (PELD).

Methods: From July 2017 to August 2018, 90 patients with lumbar intervertebral disc herniation underwent PELD surgery.

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Objective: To evaluate the clinical effect of the second puncture and injection technique during a percutaneous vertebroplasty (PVP) procedure.

Methods: Patients treated with a second puncture and injection (group A) or a single puncture and injection (group B) during PVP at our institution during 2010-2017 were reviewed. Vertebral height loss, visual analogue scale (VAS) score, Oswestry disability index (ODI), adjacent vertebral fractures, and cement leakage were compared between the groups.

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In this study, the mechanism of TDP-43 gene expression on inflammatory factors and Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) signalling pathways in ischaemic hypoxic stress dependence was investigated. Sixty SD rats were selected and divided into the control group, the osteoarthritis (OA) model group, and the TDP-43-mMSCs+OA group. In the OA model group and the TDP-43-mMSCs+OA group, OA was established by collagenase injection.

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Background: This study focused on the mechanisms where icariin inhibited chondrocyte apoptosis and angiogenesis by regulating the TDP-43 signaling pathway.

Methods: A rat osteoarthritis (OA) model was established by collagenase injection. Histological examination of the articular cartilage and synovial tissue was performed 6 weeks after operation.

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Bone marrow-derived mesenchymal stem cells (BMSCs) are widely used in tissue engineering for regenerative medicine due to their multipotent differentiation potential. However, their poor migration ability limits repair effects. Icariin (ICA), a major component of the Chinese medical herb Herba Epimedii, has been reported to accelerate the proliferation, osteogenic, and chondrogenic differentiation of BMSCs.

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A DBU-mediated synthesis of 1,3,5-trisubstituted benzenes was developed via the [2 + 4] annulation of in situ activated α,β-unsaturated carboxylic acids and α-cyano-β-methylenones. The dual role of DBU as Brønsted base and nucleophilic Lewis base is the key for the success of the reaction.

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The N-heterocyclic carbene-catalyzed [2+3] and [2+4] annulations of α-chloroaldehydes with γ-/δ-amino-α,β-unsaturated ketones were developed, giving the corresponding pyrrolidones and piperidones in good yields with exclusive trans-selectivities and excellent enantioselectivities.

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Background: High-viscosity cement (HVC) has been gradually applied in percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP). Although HVC has been reported to reduce cement leakage, different opinions exist. To assess the complications of HVC in cement leakage in the treatment of vertebral compression fractures and to evaluate the clinical effect of HVC compared with low-viscosity cement (LVC).

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Objective: To evaluate the clinical effect of ultra-early injection (before the phase of "tooth-paste-like") of low-viscosity cement in percutaneous vertebroplasty (PVP) for treating osteoporotic vertebral compression fractures (OVCFs).

Methods: Two hundred sixty-one patients who had PVP procedures with low-viscosity cement (ultra-early injection: 145, normal injection: 135) were included from July 2010 to July 2016 in our hospital. Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Cobb angle, cement leakage, and adjacent vertebral fractures were evaluated.

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Objective: This study mainly aimed to evaluate complications of cement leakage for osteoporotic thoracolumbar vertebral compression fractures by PVP using HVC, and access the clinical efficacy.

Methods: Between May 2013 and June 2015, 66 patients with osteoporotic thoracolumbar vertebral compression fractures, who underwent PVP (36 HVC and 30 LVC) in our hospital, were enrolled. Cement leakage, Visual Analog Scale (VAS), Oswestry Disability Index (ODI), refracture of the cemented vertebrae, and adjacent vertebral fractures were evaluated.

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