Publications by authors named "Jiajun Mei"

Icariside II exerts protective effects against various diseases; however, its specific effects on osteoarthritis (OA) remain unclear. Therefore, in this study, we aimed to investigate the effects of icariside II in an in vitro model of OA and analyze its action mechanisms. We established an in vitro OA model by treating a human chondrocyte cell line (CHON-001) with interleukin (IL)-1β, followed by treatment with different concentrations of icariside II.

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Group 10 metal catalysts have shown much promise for the copolymerization of nonpolar with polar alkenes to directly generate functional materials, but access to high copolymer molecular weights nevertheless remains a key challenge toward practical applications in this field. In the context of identifying new strategies for molecular weight control, we report a series of highly polarized P(V)-P(III) chelating ligands that manifest unique space filling and electrostatic effects within the coordination sphere of single component Pd polymerization catalysts and exert important influences on (co)polymer molecular weights. Single component, cationic phosphonic diamide-phosphine (PDAP) Pd catalysts are competent to generate linear, functional polyethylenes with M up to ca.

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Metal-mediated C-O bond formation is a key step in hydrocarbon oxygenation catalytic cycles; however, few examples of this reaction have been reported for low-oxidation-state complexes. Oxygen insertion into a metal-carbon bond of Cp*M(CO)(OPy)R (Cp* = η(5)-pentamethylcyclopentadienyl; R = Me, Ph; OPy = pyridine-N-oxide; M = Fe, Ru, Os) was analyzed via density functional theory calculations. Oxygen-atom insertions through a concerted single-step organometallic Baeyer-Villiger pathway and a two-step pathway via a metal-oxo intermediate were studied; calculations predict that the former pathway was lower in energy.

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Succinic acid production was inhibited by high osmotic pressure caused by the accumulation of sodium ions in the process of two-stage fermentation by Escherichia coli using Na2CO3 as the pH regulator. To enhance the resistance of this strain to osmotic stress, the possibility to isolate high NaCl-tolerant mutant strain of Escherichia coli for succinic acid production by metabolic evolution was investigated. The metabolic evolution system was used as a mutant-generating system, allowing the cells to be continuously cultured at the maximum specific growth rate.

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Cp*W(O)(2)(CH(2)SiMe(3)) (1) (Cp* = η(5)-pentamethylcyclopentadienyl) reacts with oxygen atom donors (e.g., H(2)O(2), PhIO, IO(4)(-)) in THF/water to produce TMSCH(2)OH (TMS = trimethylsilyl).

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Aim: To observe different histomorphologic changes of ulcerative colitis (UC) rats that were treated with four regulating-intestine prescriptions (FRIP), to investigate the curative effects of FRIP and to analyze their treatment mechanism.

Methods: The UC rat model was made by the method of 2,4-dinitro chloro benzene (DNCB) immunity and acetic acid local enema. Ninety-eight SD rats were randomly divided into seven groups, namely, the normal control group, model group, salicylazosulfapyridine (SASP) group, Wumeiwan (WMW) group, Baitouwengtang (BTWT) group, Senglingbaishusan (SLBSS) group, and Tongxieyaofang (TXYF) group.

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Aim: To inquire into the effects and mechanism of Zuogui Wan (Pills for Kidney Yin) on neurocyte apoptosis in nuclei of arcuate hypothalamus (ARN) of monosodium glutamate (MSG)-liver regeneration rats, and the mechanism of liver regeneration by using optic microscope, electron microscope and in situ end labeling technology to adjust nerve-endocrine-immunity network.

Methods: Neurocyte apoptosis in ARN of the experiment rats was observed by using optic microscope, electron microscope and in situ end labeling technology. Expression of TGF-beta1 in ARN was observed by using immunohistochemistry method.

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