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To improve the mechanical properties of hemicellulose hydrogel, a green, adjustable mechanical property, high swelling ratio (SR) composite hydrogel was successfully prepared by using modified lignin as a reinforcing agent. The structure and characteristics of the composite hydrogels were investigated by TGA, FTIR, SEM, rheological analysis, and SR. It can be found that the modified lignin could significantly improve the mechanical properties of the composite hydrogels. The maximum compressive stress of unmodified lignin hydrogel was 61.72 kPa and the compressive deformation was 75%. Compared with the unmodified lignin hydrogel, the mechanical properties were significantly improved, with the maximum compressive stress of the modified lignin hydrogel was 145.2 kPa and the compressive deformation was up to 90%. After adding modified lignin, the SR of the as‐prepared hydrogel was up to 155.17 g/g, which was much higher than that of unmodified lignin hydrogel (105.79 g/g). The composite hydrogel had good antioxidant properties, and the free radical removal rate can reach 85.3%, which is twice as much as that without the modified lignin. With cost‐effective lignin as a reinforcing agent, the as‐prepared hemicellulose hydrogel with adjustable mechanical properties is favorable for great application potential. [ABSTRACT FROM AUTHOR]

In this study, we synthesized Au-Cu2O core–shell nanoparticles (Au@Cu2O NPs) with epitaxial Cu2O shell, which have highly improved catalytic performances in methyl orange reduction reaction. We have obtained Au@Cu2O NPs with different sizes at low temperatures by changing the amount of Cu2+ precursor. Both Au and Cu2O are catalytic materials, especially Cu2O, as a p-type semiconductor, whose catalytic ability depends on the crystalline facets. Catalytic reduction of methyl orange (MO) was used as a model system to explore the catalytic properties of Au@Cu2O nanocomposite. In comparison to pure Au and Cu2O NPs, the catalytic performance of Au@Cu2O has a noticeable improvement. The best catalytic rate was ~ 22 times faster than that of AuNRs and ~ 4 times than that of Cu2O NPs. By studying the catalytic mechanism, it is supposed that the Schottky barrier at the Au-Cu2O interfaces leads to the charge separation, which is beneficial to catalysis. Therefore, the Au@Cu2O NPs we designed with controllable shell thickness is an ideal composite material in the catalyst domain. [ABSTRACT FROM AUTHOR]

The self-repair ability after meniscal tears is poor, leading to the development of posttraumatic osteoarthritis. Promoting the repair of meniscal injuries remains a great challenge, especially in the avascular region.Local delivery of skeletal stem cell (SSC)–derived exosomes (SSC-Exos) would promote meniscal healing and prevent secondary osteoarthritis progression.Controlled laboratory study.SSCs were isolated from bone marrow and exosomes were extracted via ultracentrifugation. The cell migration capabilities after incubation with exosomes were validated through in vitro cell culture. Full-thickness longitudinal medial meniscal tears were performed in the avascular region of 40 male Sprague-Dawley rats and 20 male New Zealand White rabbits, which were randomly divided into 2 groups: group treated with phosphate-buffered saline (GCON) and group treated with exosomes (GExosome). The effects of these treatments on meniscal healing and secondary osteoarthritis were evaluated by gross inspection, biomechanical testing, and histological assessment. RNA sequencing of in vitro cell cultures was performed to explore the underlying mechanisms.Exosomes were successfully extracted and identified. These exosomes significantly promoted cell migration capabilities in vitro (P < .01). The GExosome exhibited greater cell proliferation and tissue regeneration with type 2 collagen secretion, and a significantly higher meniscal repair score than that of the GCON at 8 weeks postoperatively (P < .05). In contrast to the degenerative changes in both the meniscus and articular cartilage of the GCON, meniscal tissue in the GExosome exhibited restoration of normal morphology with a smooth and glossy white surface and better mechanical strength at 8 weeks after meniscal repair. Both degeneration scores and synovitis scores were significantly higher in the GCON than in the GExosome (P < .05). Compared with the GCON, the expression of key genes related to cell migration, such as the chemokine family, was enhanced by exosome injection, leading to an upregulation of extracellular matrix expression while downregulating the expression of inflammation-related genes such as CD68 and the matrix metalloproteinase family.The administration of SSC-Exos effectively promoted meniscal healing in the avascular region and ameliorated secondary osteoarthritis. The effect might be attributed to inflammation modulation, promotion of cell migration, and secretion of extracellular matrix components.Injection of SSC-Exos represents a promising therapeutic option for promoting meniscal healing in the avascular region. [ABSTRACT FROM AUTHOR]

Objective: To investigation the clinical characteristics in myasthenia gravis (MG) patients with thymomas., Methods: A total of 856 MG patients admitted to the department during 2008.7 - 2010.12 were reviewed retrospectively. The patients with MG were divided into two groups based on thymic pathology, which were 162 cases with thymoma and 694 cases without thymoma. We compared the different clinical features including the gender, age of onset, MG symptoms and the incidence rate of myasthenia crisis. And the relationship between the WHO types, Maosaoka stages of thymoma and the severe of MG was also studied., Results: The percentage of thymoma-associated MG patients was 18.9 percent of hospitalized MG patients at the same period. Of the 162 thymoma-associated patients, 94 were male and 68 were female, with a ratio of 1.38:1 and a mean age of (42.9 ± 12.4) years old. Thymoma was more frequent in middle-old aged patients than in children. Compared with non-thymoma MG, more thymomatous patients showed generalised MG, but not only ocular muscles weakness (90.1% vs 62.4%, P < 0.001). There were significant differences of the incidence rate of myasthenic crisis in the two groups (14.8% vs 2.3%). (2) WHO type B2 and Maosaoka I, II thymoma were the commonest types among all potentially MG-associated thymoma. No differences of Osserman MG classification was found in thymomatous patients with different pathologic changes., Conclusions: The thymomatous MG patients had its distinctive clinical features: thymomas occurred in about 19.7% of MG patients with more men than women, more common in generalized, higher incidence of myasthenia crisis, with B2 type thymic pathology and Maosaoka I, II stages. No correlation was found between pathologic and clinical stages.

Objective: To evaluate of the role of transcranial electrical stimulation motor evoked potential (TES-MEP) in combination with cortical somatosensory evoked potential (CSEP) monitoring during the spinal surgery., Methods: TES-MEP on bilateral anterior tibial muscle and flexor hallucal brevis and CSEP on bilateral posterior tibial nerve were observed simultaneously on 293 patients during spinal surgery from July 2006 to April 2009. Intravenous anesthesia was employed in all the patients, a part of which were added low dose of sevoflurane or muscle relaxant. The results of TES-MEP, CSEP and combined monitoring were analyzed statistically. Pre-operative and post-operative motor and sensory functions of spinal cord were compared., Results: Success rate of TES-MEP, CSEP and combined monitoring was 90.8%, 96.9% and 100% respectively. For the judgment of motor function of spinal cord, the sensitivity of TES-MEP and CSEP was 100% and 89.3% respectively and the specificity of 98.4% and 96.9%. The Youden index of the two methods was 0.984 and 0.862. For sensory function, the sensitivity of them was 76.7% and 93.3% respectively and the specificity of 98.7% and 98.0%. The Youden index was 0.754 and 0.913. The sensitivity of combined monitoring was 100%, with the specificity of 96.9%. The Youden index was 0.969., Conclusions: The precision of monitoring motor function of spinal cord with TES-MEP is higher than that with CSEP, however, for sensory function, CSEP is more precise. The sensitivity and precision of combined monitoring for spinal cord function were apparently better than that of unitary TES-MEP or CSEP. The combined TES-MEP and CSEP monitoring is a relatively ideal method.