Publications by authors named "Longyu Xu"

Corticotroph pituitary neuroendocrine tumors (PitNETs), associated with Cushing's disease (CD), have limited treatment options other than surgical resection. Bone morphogenetic protein 4 (BMP4), a potential therapeutic target, is decreased in patients with CD. Previous studies have identified BMPSB4 as a potent agonist of the BMP4 signaling pathway.

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Background: Intervertebral disc degeneration (IDD) is one of the most common health problems in the elderly and a major causative factor in low back pain (LBP). An increasing number of studies have shown that IDD is closely associated with autophagy and immune dysregulation. Therefore, the aim of this study was to identify autophagy-related biomarkers and gene regulatory networks in IDD and potential therapeutic targets.

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Age-associated obesity and muscle atrophy (sarcopenia) are intimately connected and are reciprocally regulated by adipose tissue and skeletal muscle dysfunction. During ageing, adipose inflammation leads to the redistribution of fat to the intra-abdominal area (visceral fat) and fatty infiltrations in skeletal muscles, resulting in decreased overall strength and functionality. Lipids and their derivatives accumulate both within and between muscle cells, inducing mitochondrial dysfunction, disturbing β-oxidation of fatty acids, and enhancing reactive oxygen species (ROS) production, leading to lipotoxicity and insulin resistance, as well as enhanced secretion of some pro-inflammatory cytokines.

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Objectives: Our aim was to investigate the prevalence and predictive variables of sarcopenia.

Methods: We recruited participants from the Peking Union Medical College Hospital Multicenter Prospective Longitudinal Sarcopenia Study (PPLSS). Muscle mass was quantified using bioimpedance, and muscle function was quantified using grip strength and gait speed.

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In order to comprehend the influence of different "rigid-flexible" structures on the interface strength of carbon fiber(CF)/epoxy composites, CNTs was firstly chemically grafted on CFs surface, and then polyamide (PA) was grafted onto CF-CNTs surface through varying anionic polymerization time of caprolactam [CF-CNTs-PA (n = 6 h, 12 h, 24 h)]. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy indicated the successful establishment of CNTs and PA. TGA demonstrated the different grafting amounts of CF-CNTs-PA (n = 6 h, 12 h and 24 h).

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An effective approach to the fabrication of progressive epoxy nanocomposites by the incorporation of hydroxyl-terminated dendrimers functionalized graphene oxide (GO-TCT-Tris) is reported. The relationship between surface grafting, chemical construction, morphology, dispersion, and interfacial interaction as well as the corresponding mechanical properties of the composites were studied in detail. It was shown that hydroxyl-terminated triazine derivatives have been resoundingly bonded onto the GO surface through covalent bonding, which effectively improved the dispersion and compatibility of GO sheets in epoxy resin.

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Background: Ageing, chronic diseases, prolonged inactivity, and inadequate nutrition pose a severe threat to skeletal muscle health and function. To date, experimental evidence suggests that ageing-related subclinical inflammation could be an important causative factor in sarcopenia. Although inflammatory signalling has been implicated in the pathogenesis of experimental animal models of sarcopenia, few studies have surveyed the clinical association between circulating factors and muscle mass in patients before and after lifestyle interventions.

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The title compound, C10H13NO2, crystallizes with two crystallographically independent mol-ecules of similar geometry in the asymmetric unit; the six-membered oxazine rings adopts a half-chair conformation. Neither hydrogen bonds nor π-π inter-actions are observed in the crystal structure.

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