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91.
92.
Polysiloxanes have attracted considerable attention in biomedical engineering, owing to their inherent properties, including good flexibility and biocompatibility. However, their low mechanical strength limits their application scope. In this study, we synthesized a polysiloxane-based polyurethane by chemical copolymerization. A series of thermoplastic polysiloxane-polyurethanes (Si-TPUs) was synthesized using hydroxyl-terminated polydimethylsiloxane containing two carbamate groups at the tail of the polymer chains 4,4′-dicyclohexylmethane diisocyanate (HMDI) and 1,4-butanediol as raw materials. The effects of the hard-segment content and soft-segment number average molecular weight on the properties of the resulting TPUs were investigated. The prepared HMDI-based Si-TPUs exhibited good microphase separation, excellent mechanical properties, and acceptable repeatable processability. The tensile strength of SiTPU-2K-39 reached 21.5 MPa, which is significantly higher than that of other flexible polysiloxane materials. Moreover, the tensile strength and breaking elongation of SiTPU-2K-39 were maintained at 80.9% and 94.6%, respectively, after three cycles of regeneration. The Si-TPUs prepared in this work may potentially be used in gas separation, medical materials, antifouling coatings, and other applications.  相似文献   
93.
94.
The takin lungworm Varestrongylus eleguneniensis (Strongylida: Protostrongylidae) causes lethal bronchopneumonia and represents severe threats to captive and wild populations. However, until now there has been very limited information available concerning the molecular epidemiology and evolutionary biology of V. eleguneniensis. Mitochondrial genomes (mtDNAs) can provide resources for investigations in these areas and, therefore, can assist with the surveillance and control of this lungworm. Herein, the complete mtDNA of V. eleguneniensis was sequenced and characterized with Illumina pipeline analyses. This circular genome (13,625 bp) encoded twelve protein-coding genes (PCGs), two rRNAs, and twenty-two tRNAs, with notable levels of AT and GC skews. Comparative genomics revealed a purifying selection among PCGs, with cox1 and nad6 having the lowest and the highest evolutionary rate, respectively. Genome-wide phylogenies showed a close relationship between V. eleguneniensis and Protostrongylus rufescens in Strongylida. Single gene (PCGs or rRNAs)-based phylogenies indicated that cox1 and nad5 genes shared the same family-level topology with that inferred from genomic datasets, suggesting that both genes could be suitable genetic markers for evolutionary and phylogenetic studies of Strongylida species. This was the first mtDNA of any member of the genus Varestrongylus, and its comprehensive molecular characterization represents a new resource for systematic, population genetic and evolutionary biological studies of Varestrongylus lungworms in wildlife.  相似文献   
95.
Rheumatoid arthritis (RA) is a common disease worldwide and is treated commonly with methotrexate (MTX). CS12192 is a novel JAK3 inhibitor discovered by Chipscreen Biosciences for the treatment of autoimmune diseases. In the present study, we examined the therapeutic effect of CS12192 against RA and explored if the combinational therapy of CS12192 and MTX produced a synergistic effect against RA in rat collagen-induced arthritis (CIA). Arthritis was induced in male Sprague-Dawley rats by two intradermal injections of bovine type II collagen (CII) and treated with MTX, CS12192, or the combination of CS12192 and MTX daily for two weeks. Effects of different treatments on arthritis score, X-ray score, pathology, and expression of inflammatory cytokines and biomarkers were examined. We found that treatment with either CS12192 or MTX produced a comparable therapeutic effect on CIA including: (1) significantly lowering the arthritis score, X-ray score, serum levels of rheumatic factor (RF), C-reactive protein (CRP), and anti-nuclear antibodies (ANA); (2) largely alleviating histopathological damage, reducing infiltration of Th17 cells while promoting Treg cells; (3) inhibiting the expression of inflammatory cytokines and chemokines such as IL-1β, TNF-α, IL-6, CCL2, and CXCL1. All these inhibitory effects were further improved by the combinational therapy with MTX and CS12192. Of importance, the combinational treatment also resulted in a marked switching of the Th17 to Treg and the M1 to M2 immune responses in synovial tissues of CIA. Thus, when compared to the monotherapy, the combination treatment with CS12192 and MTX produces a better therapeutic effect against CIA with a greater suppressive effect on T cells and macrophage-mediated joint inflammation.  相似文献   
96.
Chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) can profile genome-wide epigenetic marks associated with regulatory genomic elements. However, conventional ChIP-seq is challenging when examining limited numbers of cells. Here, we developed a new technique by supplementing carrier materials of both chemically modified mimics with epigenetic marks and dUTP-containing DNA fragments during conventional ChIP procedures (hereafter referred to as 2cChIP-seq), thus dramatically improving immunoprecipitation efficiency and reducing DNA loss of low-input ChIP-seq samples. Using this strategy, we generated high-quality epigenomic profiles of histone modifications or DNA methylation in 10–1000 cells. By introducing Tn5 transposase-assisted fragmentation, 2cChIP-seq reliably captured genomic regions with histone modification at the single-cell level in about 100 cells. Moreover, we characterized the methylome of 100 differentiated female germline stem cells (FGSCs) and observed a particular DNA methylation signature potentially involved in the differentiation of mouse germline stem cells. Hence, we provided a reliable and robust epigenomic profiling approach for small cell numbers and single cells.  相似文献   
97.
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal interstitial lung disease with unknown etiology. Despite substantial progress in understanding the pathogenesis of pulmonary fibrosis and drug development, there is still no cure for this devastating disease. Fenbendazole (FBZ) is a benzimidazole compound that is widely used as an anthelmintic agent and recent studies have expanded the scope of its pharmacological effects and application prospect. This study demonstrated that FBZ treatment blunted bleomycin-induced lung fibrosis in mice. In vitro studies showed that FBZ inhibited the proliferation and migration of human embryo lung fibroblasts. Further studies showed that FBZ significantly inhibited glucose consumption, moderated glycolytic metabolism in fibroblasts, thus activated adenosine monophosphate-activated protein kinase (AMPK), and reduced the activation of the mammalian target of rapamycin (mTOR) pathway, thereby inhibiting transforming growth factor-β (TGF-β1)-induced fibroblast-to-myofibroblast differentiation and collagen synthesis. In summary, our data suggested that FBZ has potential as a novel treatment for pulmonary fibrosis.  相似文献   
98.
Hy-Line Brown chickens’ health is closely related to poultry productivity and it is mainly maintained by the immune system, healthy intestinal function, and microflora of chicken. Polysaccharides are biological macromolecules with a variety of activities that can be used as a potential prebiotic to improve poultry health. In this experiment, the function of Alhagi honey polysaccharides (AH) as an immunomodulator on the chicken was investigated. All chicken (120) were randomly distributed to four groups (five replicas/group, six hens/replica). A total of 0.5 mL water was taken orally by the chicken in control group. AH (0.5 mL) in different concentrations (three dosages, 0.3 g/kg, 0.6 g/k, and 1.2 g/kg) were used for the AH-0.3 g/kg, AH-0.6 g/k, and AH-1.2 g/kg group, respectively. The results showed that the growth performance of the chickens and the index of immune organs (the weight of immune organs/the body weight) were enhanced significantly after being AH-treated (p < 0.05). The content of sIgA and cytokines was upregulated remarkably in the intestine after being AH-treated (p < 0.05). The AH treatment significantly enhanced the intestinal epithelial barrier (p < 0.05). Moreover, the percentage of CD4+ and CD8+ T cells in the ileum, spleen, and serum were obviously upscaled (p < 0.05). In addition, the AH treatment significantly enhanced the production of short chain fatty acids (SCFAs) and improved the structure of gut microbiota (p < 0.05). In conclusion, we found that AH-1.2g/kg was the best dosage to improve the chicken’s health, and these data demonstrated that AH could be used as a potential tool to enhance growth performance through improving intestine function, immunity, and gut microbiome in chicken.  相似文献   
99.
100.
Nephrotoxicity is the dose-limiting factor of cisplatin treatment. Magnesium isoglycyrrhizinate (MgIG) has been reported to ameliorate renal ischemia–reperfusion injury. This study aimed to investigate the protective effect and possible mechanisms of MgIG against cisplatin-induced nephrotoxicity from the perspective of cellular pharmacokinetics. We found that cisplatin predominantly accumulated in mitochondria of renal tubular epithelial cells, and the amount of binding with mitochondrial DNA (mtDNA) was more than twice that with nuclear DNA (nDNA). MgIG significantly lowered the accumulation of cisplatin in mitochondria and, in particular, the degree of target-binding to mtDNA. MgIG notably ameliorated cisplatin-induced changes in mitochondrial membrane potential, morphology, function, and cell viability, while the magnesium donor drugs failed to work. In a mouse model, MgIG significantly alleviated cisplatin-caused renal dysfunction, pathological changes of renal tubules, mitochondrial ultrastructure variations, and disturbed energy metabolism. Both in vitro and in vivo data showed that MgIG recovered the reduction of NAD+-related substances and NAD+-dependent deacetylase sirtuin-3 (SIRT3) level caused by cisplatin. Furthermore, SIRT3 knockdown weakened the protective effect of MgIG on mitochondria, while SIRT3 agonist protected HK-2 cells from cisplatin and specifically reduced platinum-binding activity with mtDNA. In conclusion, MgIG reduces the target-binding amount of platinum to mtDNA and exerts a protective effect on cisplatin-induced renal injury through SIRT3, which may provide a new strategy for the treatment of cisplatin-induced nephrotoxicity.  相似文献   
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