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目前运动员的训练负荷是值得注意的问题，其直接影响训练效果。而心脏功能是影响运动员训练负荷的主要方面。心脏功能不仅取决于心肌细胞本身的收缩功能，同时还取决于细胞外基质成分，特别是心肌胶原纤维，其不仅具有支持和连接作用。而且在协调心肌力的传递、信息的传导、营养物质的输送等方面具有重要作用。心肌胶原网络异常。将影响心脏的收缩、舒张功能和正常心肌的电生理，还可能诱导心力衰竭的发生。但目前心肌胶原网络与心肌运动的具体关系还不确切。 相似文献
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胶原-磷酸钙复合物是最有应用前景的骨组织工程框架材料.论文通过扫描电镜、红外光谱等方法证明了复合物中的胶原与钙离子间存在配位作用.结果表明:矿化反应体系通过载钙胶原的自组装、磷酸钙矿化的相继过程,形成具有层状结构的复合物.分析了胶原生物矿化的机制. 相似文献
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在大白鼠体内模型中,对实验性切除中部1/3髌韧带后,剩余部分髌韧带早期修复过程中的细胞行为和组织学变化进行了研究。研究表明:髌韧带存在着内在修复能力,在本模型中伤口的修复是从伤口中部开始并向腹侧和背侧延伸。伤口的修复先是伤口周边的细胞移行进伤口,然后到达目的地的细胞开始分泌胶原蛋白,并形成新生的胶原纤维。纤维粘连蛋白在损伤修复的早期存在表达,可能是充当使参与修复的细胞从伤口的边缘移行到伤口中央的生物桥梁。伤口中的细胞和胶原纤维修复到接近组织学正常的时间约需6至9个月。 相似文献
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Alida M Bailleul Wenxia Zheng John R Horner Brian K Hall Casey M Holliday Mary H Schweitzer 《国家科学评论(英文版)》2020,7(4):815
A histological ground-section from a duck-billed dinosaur nestling (Hypacrosaurus stebingeri) revealed microstructures morphologically consistent with nuclei and chromosomes in cells within calcified cartilage. We hypothesized that this exceptional cellular preservation extended to the molecular level and had molecular features in common with extant avian cartilage. Histochemical and immunological evidence supports in situ preservation of extracellular matrix components found in extant cartilage, including glycosaminoglycans and collagen type II. Furthermore, isolated Hypacrosaurus chondrocytes react positively with two DNA intercalating stains. Specific DNA staining is only observed inside the isolated cells, suggesting endogenous nuclear material survived fossilization. Our data support the hypothesis that calcified cartilage is preserved at the molecular level in this Mesozoic material, and suggest that remnants of once-living chondrocytes, including their DNA, may preserve for millions of years. 相似文献
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The misfolding of amyloid-β (Aβ) peptides from the natural unfolded state to β-sheet structure is a critical step, leading to abnormal fibrillation and formation of endogenous Aβ plaques in Alzheimer''s disease (AD). Previous studies have reported inhibition of Aβ fibrillation or disassembly of exogenous Aβ fibrils in vitro. However, soluble Aβ oligomers have been reported with increased cytotoxicity; this might partly explain why current clinical trials targeting disassembly of Aβ fibrils by anti-Aβ antibodies have failed so far. Here we show that Au23(CR)14 (a new Au nanocluster modified by Cys-Arg (CR) dipeptide) is able to completely dissolve exogenous mature Aβ fibrils into monomers and restore the natural unfolded state of Aβ peptides from misfolded β-sheets. Furthermore, the cytotoxicity of Aβ40 fibrils when dissolved by Au23(CR)14 is fully abolished. More importantly, Au23(CR)14 is able to completely dissolve endogenous Aβ plaques in brain slices from transgenic AD model mice. In addition, Au23(CR)14 has good biocompatibility and infiltration ability across the blood–brain barrier. Taken together, this work presents a promising therapeutics candidate for AD treatment, and manifests the potential of nanotechnological approaches in the development of nanomedicines. 相似文献
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Yong-liang Zhuang Xue Zhao Ba-fang Li 《Journal of Zhejiang University. Science. B》2009,10(8):572-579
To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical
scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology
(RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (T) 48.77 °C, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were
important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography
(HPLC), and three fractions (HF-1>3000 Da, 1000 Da<HF-2<3000 Da, and HF-3<1000 Da) were collected. The HF-2 fraction had the
highest hydroxyl radical scavenging activity with the highest yield compared with the other two fractions. Furthermore, HF-2
also showed the strongest Cu2+-chelating ability and the best tyrosinase-inhibitory activity.
Project (No. 2008BAD94B07) supported by the Hi-Tech Research and Development Program (863) of China 相似文献
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BackgroundOsteoarthritis (OA) is a form of arthritis due to degradation of articular cartilage. OA is associated with stiffness, joint pain, and dysfunction, affecting adults worldwide. Galangin is a bioactive flavonoid that exerts several therapeutic and biological activities. Anti-hyperglycemic, anti-inflammatory, anti-cancer, and anti-apoptotic activities of galangin have been reported in several studies. In the present study, rats were divided into normal control, OA (control), galangin 10 mg/kg (low-dose), galangin 100 mg/kg (high-dose), and celecoxib 30 mg/kg (positive control) groups. All doses were administered orally for 14 consecutive days. The urinary type II collagen (µCTX-II) level as well as reactive oxygen species, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, superoxide dismutase, catalase, lipid peroxidation, reduced glutathione, and glutathione peroxidase levels were measured. In addition, the CTX-II mRNA and protein expression levels were measured.ResultsGalangin supplementation significantly reduced the µCTX-II level compared with controls. Galangin treatment significantly reduced reactive oxygen species, lipid peroxidation, interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha levels, but increased catalase, superoxide dismutase, glutathione peroxidase, and reduced glutathione levels. Galangin treatment significantly reduced the CTX-II mRNA and protein expression levels. The low CTX-II level in tissue indicated the inhibition of cartilage degradation.ConclusionsIn summary, supplementation with galangin was effective against OA. The identification of potential therapeutic agents that inhibit inflammation may be useful for the management and prevention of OA.How to cite: Su Y, Shen L, Xue J, et al. Therapeutic evaluation of galangin on cartilage protection and analgesic activity in a rat model of osteoarthritis. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.05.005 相似文献
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To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (7) 48.77 ℃, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da相似文献
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