Piezoelectric Nanostructured Surface for Ultrasound-Driven Immunoregulation to Rescue Titanium Implant Infection

Treating bacterial biofilm infections on implanted materials remains challenging in clinical practice, as bacteria can be resistant by weakening the host defense from immune cells like macrophages. Herein, a metal-piezoelectric hetero-nanostructure with mechanical energy-driven antimicrobial property is in situ constructed on the Ti implant. Under ultrasonic irradiation, the formed piezotronic Ti (piezoTi) can promote the generation of reactive oxygen species (ROS) by facilitating local charge transfer at the surface, thus leading to piezodynamic killing of Staphylococcus aureus (S. aureus) while downregulating biofilm-forming genes. In addition, the stimulated macrophages on piezoTi display potent phagocytosis and anti-bacterial activity through the activation of PI3K-AKT and MAPK pathway. As a demonstration, one-time ultrasound irradiation of piezoTi pillar implanted in an osteomyelitis model efficiently eliminates the S. aureus biofilm infection and rescues the implant with enhanced osteointegration. By the synergistic effect of ultrasound-driven piezodynamic therapy and immuno-regulation, the proposed piezoelectric nanostructured surface can endow Ti implants with highly efficient antibacterial performance in an antibiotic-free, noninvasive, and on-demand manner.     

山慈菇多糖的免疫调节作用及对小鼠骨肉瘤细胞S180体内生长抑制作用

目的：探讨山慈菇多糖的免疫调节作用及对小鼠骨肉瘤细胞S180的抑制作用。方法：噻唑蓝法及吞噬中 性红法测定小鼠脾淋巴细胞增殖能力及脾巨噬细胞活性;体内肿瘤抑制实验检测山慈菇多糖对S180荷瘤小鼠肿瘤 生长、脾脏指数和胸腺指数的影响;流式细胞术及酶联免疫吸附测定法检测山慈菇多糖对S180荷瘤小鼠T淋巴细胞 亚群及血清细胞因子水平的影响。结果：山慈菇多糖可以增强淋巴细胞增殖能力和巨噬细胞活性;同时,山慈菇多 糖也可以抑制S180荷瘤小鼠肿瘤生长,增加小鼠脾脏指数和胸腺指数;此外,山慈菇多糖还可以增加荷瘤小鼠CD4 ＋、CD8＋ T细胞浓度,提高CD4＋/CD8＋比值及白细胞介素-2、肿瘤坏死因子-α、干扰素-γ水平。结论：山慈菇 多糖具有明显的肿瘤抑制作用,其对肿瘤细胞生长的抑制作用与提高免疫能力有关。     

甘薯多糖的抗肿瘤研究

采用水提醇沉法从“广薯98”中提取甘薯粗多糖,通过灌胃给药,研究了甘薯多糖对荷瘤小鼠(H22)的抑瘤率、存活期和脾脏指数、胸腺指数、腹腔巨噬细胞活性的影响。其研究结果显示:甘薯多糖对H22实体瘤小鼠具有明显的抑瘤作用(P<0.05),对H22腹水瘤小鼠具有明显的延长存活期作用(P<0.05);甘薯多糖能明显增加H22实体瘤小鼠的脾脏指数、胸腺指数(P<0.05或P<0.01),能明显增强H22实体瘤小鼠的腹腔巨噬细胞活性(P<0.01)。表明甘薯多糖对H22荷瘤小鼠具有明显的抗肿瘤作用。     

乳铁蛋白对肠道屏障保护作用的研究进展

完整的肠道屏障是维持肠道健康的先行和必要条件。乳铁蛋白因其具有多种生物活性而备受推崇。近年来,国内外大量研究报道了乳铁蛋白通过修复肠黏膜、调节免疫功能和肠道菌群等来维持肠道稳态。该研究主要对乳铁蛋白的生物学特性、乳铁蛋白对肠屏障的作用以及乳铁蛋白的应用进行了综述。     

鹰嘴豆多肽抗疲劳活性

目的:提高鹰嘴豆的附加值。方法:进行小鼠负重游泳试验,测定免疫活性,分析疲劳相关生化指标。结果:负重游泳试验中,鹰嘴豆多肽喂养组小鼠游泳时间极显著长于对照组(P<0.01),鹰嘴豆多肽极显著降低了小鼠血液中尿素氮和血乳酸水平,极显著提高了肝糖原、肌糖原和胰岛素含量(P<0.01)。鹰嘴豆多肽还可显著提高超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)的活性。此外,补充鹰嘴豆多肽可以通过增加小鼠的吞噬细胞活性、刺激sIgA分泌和减少促炎细胞因子来提高免疫力。结论:鹰嘴豆多肽对小鼠具有较强的抗疲劳作用。     

Health-promoting effects of dietary polysaccharide extracted from Dendrobium aphyllum on mice colon,including microbiota and immune modulation

The health-promoting effects of a polysaccharide (DAP) purified from Dendrobium aphyllum, on mice colon were investigated. The results indicated that consumption of DAP facilitated the differentiation degree of CD4⁺ T cells to Th₁, Th₁₇ and Treg cells; and depressed the differentiation degree to Th₂ cells, since DAP up-regulated IL-6 expression (from 1.08 ± 0.24 to 3.40 ± 0.36). Besides, oral administration of DAP reduced the gastrointestinal transit time from 255 ± 1.21 to 164 ± 0.46 min, decreased the pH from 6.70 ± 0.27 to 5.54 ± 0.31, improved faecal water-binding capability from 59.4% ± 0.35 to 63.5% ± 0.22. Additionally, the increase in four health-promoting short chain fatty acids were observed, which might result from the enrichment of the relative abundance of health-promoting microbiota genera, including Porphyromonadaceae and Ruminococcaceae. The DAP-induced up-regulation of the genus Erysipelotrichaceae might be related to the homeostasis in both Th₁/Th₂ and Treg/Th₁₇.     

乳酸菌胞外多糖肠道黏附及免疫调节作用研究进展

乳酸菌作为公认的食品级益生菌,在医学、食品科学及人类健康中发挥重要作用。乳酸菌的胞外多糖作为其主要的细胞外分泌物与其相应生物学功能的发挥密切相关。本文旨在从乳酸菌胞外多糖的理化特性和分子结构方面入手探究其调节免疫的机制,并总结乳酸菌胞外多糖在调节胃肠道功能和进入体内后的免疫调节等方面的特性。以期为乳酸菌胞外多糖的研究和应用奠定理论基础。     

益生菌在改善阿尔茨海默病中的研究进展

阿尔茨海默病（Alzheimer’s disease,AD）是目前世界上患者数量多、影响范围广的一种神经退行性疾病,其致病机理至今仍未完全解析。大量研究表明肠道菌群可通过肠-脑轴调节机体大脑的发育与健康。益生菌是一类对人体有益的、活的微生物,对维持肠道微生态平衡具有重要的意义。近年来,益生菌及其代谢产物或益生菌发酵食品在改善AD等神经退行性疾病方面受到了极大的关注。本文综述了近5 年来国内外利用单种、多种益生菌、益生菌发酵食品、益生菌与其他药物联合用于改善AD的研究进展,并阐述了相关作用机制和存在的问题,以期为益生菌用于预防和治疗AD提供新的思路。     

金圣草黄素相关药理作用机制的研究进展

金圣草黄素是一种天然黄酮化合物,存在于多种中药和药用植物体内,具有良好的新药候选化合物潜力。近年来,随着金圣草黄素及其糖苷类衍生物的药效作用和药理机制研究逐渐增多,该化合物的药理作用特点逐渐显现,尤其是在抗肿瘤、抗氧化损伤和抗炎免疫调节等多个领域显示出良好的新药候选化合物开发潜力。本文通过对金圣草黄素的药理作用和机制进行简要综述,为研究者了解该化合物的药理作用特点,同时也为基于该成分的新药开发提供借鉴和参考。