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511.
Salmonella typhimurium infection is associated with gastrointestinal disorder and cellular injury in the liver of both humans and animals. Cinnamaldehyde, the main component of essential oil from cinnamon, has been reported to have anti-inflammatory, anti-oxidative, and anti-apoptotic effects. However, it remains unknown whether cinnamaldehyde can alleviate Salmonella typhimurium infection-induced liver injury in mice. In the present study, we found that cinnamaldehyde attenuated Salmonella typhimurium-induced body weight loss, the increase of organ (liver and spleen) indexes, hepatocyte apoptosis, and the mortality rate in mice. Further study showed that cinnamaldehyde significantly alleviated Salmonella typhimurium-induced liver injury as shown by activities of alanine transaminase, aspartate transaminase, and myeloperoxidase, as well as malondialdehyde. The increased mRNA level of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and IFN-γ) and chemokines (CCL2 and CCL3) induced by Salmonella typhimurium were significantly abolished by cinnamaldehyde supplementation. These alterations were associated with a regulatory effect of cinnamaldehyde on TLR2, TLR4, and MyD88. 16S rDNA sequence analysis showed that Salmonella typhimurium infection led to upregulation of the abundances of genera Akkermansia, Bacteroides, Alistipes, Muribaculum, and Prevotellaceae UCG-001, and downregulation of the abundances of genera Lactobacillus, Enterorhabdus, and Eggerthellaceae (unclassified). These alterations were reversed by cinnamaldehyde supplementation. In conclusion, cinnamaldehyde attenuated the inflammatory response, oxidative stress, and apoptosis in the liver of Salmonella typhimurium-infected mice. Supplementation of cinnamaldehyde might be a preventive strategy to alleviate liver injury caused by Salmonella typhimurium infection in humans and animals.  相似文献   
512.
Sinomenine is the main component of the vine Sinomenium acutum. It was first isolated in the early 1920s and has since attracted special interest as a potential anti-rheumatoid arthritis (RA) agent, owing to its successful application in traditional Chinese medicine for the treatment of neuralgia and rheumatoid diseases. In the past few decades, significant advances have broadened our understanding of the molecular mechanisms through which sinomenine treats RA, as well as the structural modifications necessary for improved pharmacological activity. In this review, we summarize up-to-date reports on the pharmacological properties of sinomenine in RA treatment, document their underlying mechanisms, and provide an overview of promising sinomenine derivatives as potential RA drug therapies.  相似文献   
513.
Correlations between plasma concentrations of imatinib and sunitinib with efficacy and toxicity have been established. It is crucial to develop a sensitive and precise method for determining the plasma concentrations of imatinib and sunitinib, along with their active metabolites, to facilitate therapeutic drug monitoring and individualized therapy. Plasma samples were separated on an Agilent ZORBAX SB-C18 chromatographic column using gradient elution. Quantification was performed using a mass spectrometer equipped with electrospray ionization in multiple reaction monitoring. The analysis time was 18 min per run, with all analytes and internal standards eluting within 8 min. The calibration range was 25–4000 ng/mL for imatinib, 5–800 ng/mL for N-desmethyl imatinib (CGP74588), and 2.5–400 ng/mL for sunitinib and N-desethyl sunitinib (SU12662). Intra- and inter-assay precision were both below 15%, and accuracy ranged between 90.0% and 101.9%. The method was successfully applied to determine blood samples from 120 patients with gastrointestinal stromal tumors who received imatinib (n = 115) and sunitinib (n = 5). It has been validated as linear, accurate, precise, and robust, making it suitable for therapeutic drug monitoring of imatinib and sunitinib in routine clinical practice.  相似文献   
514.
Wang  Teng  Lyu  Chun-yi  Jiang  Yue-hua  Dong  Xue-yan  Wang  Yan  Li  Zong-hong  Wang  Jin-xin  Xu  Rui-rong 《Molecular diversity》2021,25(4):2351-2365
Molecular Diversity - A poor prognosis, relapse and resistance are burning issues during adverse-risk acute myeloid leukaemia (AML) treatment. As a natural medicine, Scutellaria barbata D. Don...  相似文献   
515.
固体氧化物燃料电池(solid oxide fuel cell,SOFC)是一种清洁高效的发电装置,其运行中的性能衰减受到众多因素的影响,如何分辨这些因素的贡献、并在此基础上确定衰减的主导因素,对于更有针对性地提升SOFC的运行寿命至关重要.广泛的测试结果表明,SOFC的电化学性能在运行初期(约前100 h)会发生最为...  相似文献   
516.
Limbal stem cell deficiency causes conjunctivalization characterized by the covering of the corneal surface with conjunctival epithelium. However, the driving force for the encroachment of these conjunctival cells is unclear. Conjunctival stem cells are bipotent stem cells that can proliferate and differentiate into conjunctival epithelial cells and goblet cells to maintain regeneration of the conjunctival epithelium. Here, we show a robust proliferative response of conjunctival stem cells and upregulation of Wnt2b and Wnt3a gene expression in the conjunctivae of mice with induced limbal stem cell deficiency. Topical application of the Wnt/β-catenin signaling activator CHIR resulted in increased proliferation of ΔNp63α-positive stem cells in the basal layers of the bulbar and forniceal conjunctivae and enhanced invasion of conjunctival epithelial and goblet cells into the corneal surface. We also found that in cultures of stem cells isolated from the human conjunctiva, Wnt/β-catenin pathway activation improved the expansion of the ΔNp63α/ABCG2 double-positive cell population by promoting the proliferation and preventing the differentiation of these cells. These expanded stem cells formed a stratified epithelium containing goblet cells under airlift culture conditions. Our data reveal that Wnt/β-catenin signaling contributes to the pathological process of limbal stem cell deficiency by promoting the self-renewal of conjunctival stem cells and suggest that these cells are a driving force in corneal conjunctivalization.Subject terms: Self-renewal, Stem-cell research, Experimental models of disease  相似文献   
517.
采用动态流变学测试和结晶动力学的方法研究了两种分子量的高密度聚乙烯(HDPE)与茂金属线型低密度聚乙烯(m-LLDPE)共混体系的相容性.流变学研究表明,HDPE/m-LLDPE共混物在低ω区域lgG′-lgω关系曲线偏离线性规律,在熔融态为非均相体系.DSC分析发现HDPE/m-LLDPE共混物体系中HDPE的熔点随着m-LLDPE含量的增多而逐渐下降,说明HDPE与m-LLDPE二者具有机械相容性.当HDPE在m-LLDPE的熔体中等温结晶,分子量较高的HDPE结晶速率与纯HDPE相近,m-LLDPE的含量变化对Avrami指数n的影响不大;分子量较低的HDPE指数n和半结晶时间t1/2随m-LLDPE含量的增加逐渐增大,结晶速率随着m-LLDPE含量的增加逐渐下降,表明熔融态的m-LLDPE和HDPE存在着较强的分子间相互作用,二者具有一定的相容性.  相似文献   
518.
POE-g-PMAH反应性增容PA1010/PP共混物的性能研究   总被引:2,自引:2,他引:2  
乙烯-辛烯共聚物-g-聚马来酸酐(POE-g-PMAH)作为反应性增容剂,采用熔体共混的方法制备了PA1010/PP共混物,通过扫描电镜(SEM)、力学性能、傅立叶变换红外光谱(FTIR)和示差扫描量热(DSC)测试,研究了POE-g-PMAH对PA1010/PP共混物的增容作用.结果表明,POE-g-PMAH的加入可以减小共混物的相区尺寸,当PA1010/PP/POE-g-PMAH=70/30/15时,分散相尺寸小而均匀;FTIR结果表明接枝在POE上的马来酸酐基团和PA1010在熔融共混期间发生了化学反应;DSC研究结果表明共混体系中PA1010和PP的结晶温度和结晶度随POE-g-PMAH的加入而降低,表明POE-g-PMAH的增容作用对PA1010和PP的结晶有抑制作用.力学性能测试结果表明随着POE-g-PMAH的增加,共混物的冲击强度逐渐增加,当POE-g-PMAH含量增加到15%时,干态冲击强度达到21.13 kJ/m2,是不加增容剂的3.1倍,而拉伸和弯曲强度可以保持较高水平.POE-g-PMAH的增容机理在于其支链中的马来酸酐能与PA1010中的胺基(NH2—)发生化学反应,而主链POE与PP有较好的亲和性,从而降低界面张力,减少相区尺寸,大幅度提高力学性能.  相似文献   
519.
The importance of modulating the intensity of Wnt signaling has been highlighted in various biological models, but their mechanisms remain unclear. In this study, we found that Ryk—an atypical Wnt receptor with a pseudokinase domain—has a Wnt-modulating effect in bone marrow stromal cells to control hematopoiesis-supporting activities. We first found that Ryk is predominantly expressed in the mesenchymal stromal cells (MSCs) of the bone marrow (BM) compared with hematopoietic cells. Downregulation of Ryk in MSCs decreased their clonogenic activity and ability to support self-renewing expansion of primitive hematopoietic progenitors (HPCs) in response to canonical Wnt ligands. In contrast, under high concentrations of Wnt, Ryk exerted suppressive effects on the transactivation of target genes and HPC-supporting effects in MSCs, thus fine-tuning the signaling intensity of Wnt in BM stromal cells. This ability of Ryk to modulate the HPC-supporting niche activity of MSCs was abrogated by induction of deletion mutants of Ryk lacking the intracellular domain or extracellular domain, indicating that the pseudokinase-containing intracellular domain mediates the Wnt-modulating effects in response to extracellular Wnt ligands. These findings indicate that the ability of the BM microenvironment to respond to extracellular signals and support hematopoiesis may be fine-tuned by Ryk via modulation of Wnt signaling intensity to coordinate hematopoietic activity.Subject terms: Mesenchymal stem cells, Mesenchymal stem cells, Haematopoietic stem cells  相似文献   
520.
建立高效液相色谱法同时测定白花蛇舌草药材中对香豆酸和熊果酸含量的方法。采用Eclipse SB–C18色谱柱(250 mm×4.6 mm,5μm),以甲醇–0.05%甲酸梯度洗脱,流量1 m L/min,对香豆酸和熊果酸的检测波长分别为310 nm和210 nm,柱温30℃。对香豆酸和熊果酸含量分别在0.001 79~0.028 64 mg/m L和0.021 3~0.340 8 mg/m L范围内与色谱峰面积呈良好的线性关系,线性相关系数r分别为0.999 8,0.999 6。对香豆酸和熊果酸的平均加标回收率分别为98.59%,98.23%,测定结果的相对标准偏差分别为0.81%,0.94%(n=6)。样品溶液在24 h内稳定。该方法适用于白花蛇舌草药材中对香豆酸和熊果酸的含量测定。  相似文献   
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