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121.
龙血树(Dracaena Vandelli ex Linnaeus)是一种热带特有的珍稀药用植物。傣族贝叶经记载龙血树叶具有和血竭相似的医疗功效,且市场反馈显示对糖尿病有一定治疗效果,但其降血糖机制尚未揭示。将柬埔寨龙血树叶在L6大鼠成肌细胞降糖活性模型指导下,经热水浸提、醇沉制备粗多糖,再经Sevag法除蛋白、A-722MP阴离子交换树脂脱色后,上DEAE-52纤维素柱层析和Sephacryl S-100HR凝胶柱分离纯化,得到单一活性组分LZS,利用紫外、红外、核磁共振波谱以及HPAEC-PAD色谱法对LZS的结构进行鉴定。活性组分LZS为7种单糖和柠檬酸组成的一种多糖衍生物,单糖组成为:果糖、葡萄糖、半乳糖、阿拉伯糖、鼠李糖、甘露糖、木糖,摩尔比为54.3∶29.5∶6.9∶6.2∶2.1∶0.7∶0.4,主要由果糖和葡萄糖聚合而成,龙血树叶多糖结构新颖,具有明显的细胞活性。实验结果初步阐明了龙血树叶降糖活性的化学本质,为龙血树叶的利用提供了科学依据。 相似文献
122.
Glioblastomas (GBMs) are highly lethal primary brain tumors. Despite current therapeutic advances in other solid cancers, the treatment of these malignant gliomas remains essentially palliative. GBMs are extremely resistant to conventional radiation and chemotherapies. We and others have demonstrated that a highly tumorigenic subpopulation of cancer cells called GBM stem cells (GSCs) promotes therapeutic resistance. We also found that GSCs stimulate tumor angiogenesis by expressing elevated levels of VEGF and contribute to tumor growth, which has been translated into a useful therapeutic strategy in the treatment of recurrent or progressive GBMs. Furthermore, stem cell-like cancer cells (cancer stem cells) have been shown to promote metastasis. Although GBMs rarely metastasize beyond the central nervous system, these highly infiltrative cancers often invade into normal brain tissues preventing surgical resection, and GSCs display an aggressive invasive phenotype. These studies suggest that targeting GSCs may effectively reduce tumor recurrence and significantly improve GBM treatment. Recent studies indicate that cancer stem cells share core signaling pathways with normal somatic or embryonic stem cells, but also display critical distinctions that provide important clues into useful therapeutic targets. In this review, we summarize the current understanding and advances in glioma stem cell research, and discuss potential targeting strategies for future development of anti-GSC therapies. 相似文献
123.
Wei Wang Shi-Chong Qiao Xiang-Bing Wu Bao Sun Jin-Gang Yang Xing Li Xiao Zhang Shu-Jiao Qian Ying-Xin Gu Hong-Chang Lai 《Cell death & disease》2021,12(7)
With an increasing aging society, China is the world’s fastest growing markets for oral implants. Compared with traditional oral implants, immediate implants cause marginal bone resorption and increase the failure rate of osseointegration, but the mechanism is still unknown. Therefore, it is important to further study mechanisms of tension stimulus on osteoblasts and osteoclasts at the early stage of osseointegration to promote rapid osseointegration around oral implants. The results showed that exosomes containing circ_0008542 from MC3T3-E1 cells with prolonged tensile stimulation promoted osteoclast differentiation and bone resorption. Circ_0008542 upregulated Tnfrsf11a (RANK) gene expression by acting as a miR-185-5p sponge. Meanwhile, the circ_0008542 1916-1992 bp segment exhibited increased m6A methylation levels. Inhibiting the RNA methyltransferase METTL3 or overexpressing the RNA demethylase ALKBH5 reversed osteoclast differentiation and bone resorption induced by circ_0008542. Injection of circ_0008542 + ALKBH5 into the tail vein of mice reversed the same effects in vivo. Site-directed mutagenesis study demonstrated that 1956 bp on circ_0008542 is the m6A functional site with the abovementioned biological functions. In conclusion, the RNA methylase METTL3 acts on the m6A functional site of 1956 bp in circ_0008542, promoting competitive binding of miRNA-185-5p by circ_0008542, and leading to an increase in the target gene RANK and the initiation of osteoclast bone absorption. In contrast, the RNA demethylase ALKBH5 inhibits the binding of circ_0008542 with miRNA-185-5p to correct the bone resorption process. The potential value of this study provides methods to enhance the resistance of immediate implants through use of exosomes releasing ALKBH5.Subject terms: Epigenetics, Predictive markers 相似文献
124.
ZHENG LianBin LI YongLan XI HuanJiu YU KeLi LU ShunHua SHI Rui WEN YouFeng BAO JingPing ZHANG XingHua LI YuLing REN Fu XU GuoChang 《中国科学:生命科学英文版》2015,58(2):215-217,1,3
<正>Dear Editor,Shortly after initiating the"Physical Anthropological Research on Han Chinese"research project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable 相似文献
125.
Kai Bao Xiaofei Li Tetsuhiro Kajikawa Abe Toshiharu Nathalie Selevsek Jonas Grossmann George Hajishengallis Nagihan Bostanci 《Proteomics》2020,20(3-4)
Understanding the progression of periodontal tissue destruction is at the forefront of periodontal research. The authors aimed to capture the dynamics of gingival tissue proteome during the initiation and progression of experimental (ligature‐induced) periodontitis in mice. Pressure cycling technology (PCT), a recently developed platform that uses ultra‐high pressure to disrupt tissues, is utilized to achieve efficient and reproducible protein extraction from ultra‐small amounts of gingival tissues in combination with liquid chromatography‐tandem mass spectrometry (MS). The MS data are processed using Progenesis QI and the regulated proteins are subjected to METACORE, STRING, and WebGestalt for functional enrichment analysis. A total of 1614 proteins with ≥2 peptides are quantified with an estimated protein false discovery rate of 0.06%. Unsupervised clustering analysis shows that the gingival tissue protein abundance is mainly dependent on the periodontitis progression stage. Gene ontology enrichment analysis reveals an overrepresentation in innate immune regulation (e.g., neutrophil‐mediated immunity and antimicrobial peptides), signal transduction (e.g., integrin signaling), and homeostasis processes (e.g., platelet activation and aggregation). In conclusion, a PCT‐assisted label‐free quantitative proteomics workflow that allowed cataloging the deepest gingival tissue proteome on a rapid timescale and provided novel mechanistic insights into host perturbation during periodontitis progression is applied. 相似文献
126.
127.
Zhuona Xi Yahong Qiao Jifang Wang Hongjian Su Zhen Bao Hongyan Li Xiaoming Liao Xiaolan Zhong 《Journal of cellular and molecular medicine》2020,24(2):1451-1459
The beneficial function of gastrodin towards many inflammatory diseases has been identified. This study designed to see the influence of gastrodin in a cell model of chronic obstructive pulmonary disease (COPD). MRC‐5 cells were treated by LPS, before which gastrodin was administrated. The effects of gastrodin were evaluated by conducting CCK‐8, FITC‐PI double staining, Western blot, qRT‐PCR and ELISA. Besides this, the downstream effector and signalling were studied to decode how gastrodin exerted its function. And dual‐luciferase assay was used to detect the targeting link between miR‐103 and lipoprotein receptor‐related protein 1 (LRP1). LPS induced apoptosis and the release of MCP‐1, IL‐6 and TNF‐α in MRC‐5 cells. Pre‐treating MRC‐5 cells with gastrodin attenuated LPS‐induced cell damage. Meanwhile, p38/JNK and NF‐κB pathways induced by LPS were repressed by gastrodin. miR‐103 expression was elevated by gastrodin. Further, the protective functions of gastrodin were attenuated by miR‐103 silencing. And LRP1 was a target of miR‐103 and negatively regulated by miR‐103. The in vitro data illustrated the protective function of gastrodin in LPS‐injured MRC‐5 cells. Gastrodin exerted its function possibly by up‐regulating miR‐103 and modulating p38/JNK and NF‐κB pathways. 相似文献
128.
Deformable energy storage devices are needed to power next‐generation wearable electronics that interface intimately with human skin. Currently, deformable energy storage devices demonstrate poor performance compared to their rigid lithium‐ion counterparts, forcing wearable manufacturers to design their devices around bulky battery compartments. However, technological advances to create deformable batteries at the component and device level have yielded continuous improvement in stretchable batteries over the last five years. In this Essay, the major strategies at the component and device level that have been successfully employed to create stretchable batteries are reviewed. The outstanding challenges facing deformable energy storage are also discussed, namely, energy density, packaging, delamination, device integration, and manufacturing. This Essay will give researchers who are interested in contributing to the development of deformable batteries a cursory understanding of the most successful strategies to date, and provide insights into the most important directions to pursue in the future. 相似文献
129.
目的:研究白蛋白静脉滴注联合茵栀黄颗粒对新生儿黄疸血清碱性磷酸酶(alkaline phosphatase,AKP)、总胆汁酸(totalbileacids,TBA)、游离脂肪酸(free fatty acid,FFA)、γ-谷氨酰基转移酶(γ-glutamyltransferase,γ-GT)、超敏C-反应蛋白(hypersensitive C-reactive protein, HS-CRP)的影响。方法:选择2016年1月~2019年1月我院收治的95例新生儿病理性黄疸患儿,随机分为两组。对照组服用茵栀黄颗粒治疗,观察组在服用茵栀黄的基础上静脉滴注白蛋白治疗。检测两组的血清间接胆红素(indirectreacting bilirubin,,IBIL)、总胆红素(total bilirubin,TBIL)和AKP、TBA、FFA、y-GT、HS-CRP水平。结果:观察组的有效率明显高于对照组(P0.05);两组治疗后的血清IBIL、TBIL水平明显降低(P0.05),观察组的IBIL、TBIL水平明显低于对照组(P0.05);两组治疗后的血清AKP、TBA、FFA、γ-GT、HS-CRP水平明显降低(P0.05),观察组的血清AKP、TBA、FFA、γ-GT、HS-CRP水平明显低于对照组(P0.05)。结论:白蛋白静脉滴注联合茵栀黄颗粒对新生儿黄疸的治疗效果良好,有助于促进血清胆红素和其他血清学相关指标恢复正常,且安全性好。 相似文献
130.
目的:探讨门冬胰岛素联合甘精胰岛素对新诊断2型糖尿病患者血清炎性因子、血糖及血脂水平的影响。方法:选取我院2017年3月~2019年3月收治的100例新诊断2型糖尿病患者,将其随机分为研究组和对照组,每组50例患者。对照组患者给予门冬胰岛素治疗,研究组患者给予门冬胰岛素联合甘精胰岛素治疗,对比两组患者治疗前后血清炎性因子、血糖及血脂水平的变化。结果:治疗后,两组患者糖化血红蛋白(hemoglobin A1c,HbA1c)、空腹血糖(fasting plasma glucose,FPG)、餐后2h血糖(2h postprandial blod glucose,2hPBG)、血清肿瘤坏死因子(Tumor necrosis factor,TNF-α)、高敏C反应蛋白(high-sensitive C-reactive protein,hs-CRP)水平均较治疗前明显降低(P0.05),且研究组患者以上指标均显著低于对照组(P0.05);两组患者治疗后总胆固醇(Total Cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low-density lipoprotein cholesterol,LDL-C)水平均较治疗前明显降低,高密度脂蛋白胆固醇(High-density lipoprotein cholesterol,HDL-C)明显升高(P0.05),且研究组以上指标的改善程度均优于对照组(P0.05)。研究组患者的胰岛素用量明显少于对照组(P0.05),患者血糖首次达标时间明显短于对照组(P0.05)。结论:门冬胰岛素联合甘精胰岛素适用于新诊断2型糖尿病患者,可有效降低血糖、血脂、血清TNF-α和hs-CRP水平。 相似文献