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81.
Yue Liu Chang Liu Chang Wang Qian Zhang Xingyuan Qu Chen Liang Chao Si Lei Wang 《International journal of molecular sciences》2022,23(22)
Periodontitis is a chronic inflammatory disease that is considered to be the main cause of adult tooth loss. Diabetes mellitus (DM) has a bidirectional relationship with periodontitis. Interleukin-1β (IL-1β) is an important pre-inflammatory factor, which participates in the pathophysiological process of periodontitis and diabetes. The interleukin-1 receptor antagonist (IL-1ra) is a natural inhibitor of IL-1, and the balance between IL-1ra and IL-1β is one of the main factors affecting chronic periodontitis (CP) and diabetes. The purpose of this study is to develop a drug carrier that is safe and nontoxic and can effectively release IL-1ra, which can effectively slow down the inflammation of periodontal tissues with diabetes, and explore the possibility of lowering the blood sugar of this drug carrier. Therefore, in this experiment, a temperature-sensitive hydrogel loaded with IL-1ra was prepared and characterized, and its anti-inflammatory effect in high-sugar environments in vivo and in vitro was evaluated. The results showed that the hydrogel could gel after 5 min at 37 °C, the pore size was 5–70 μm, and the cumulative release of IL-1ra reached 83.23% on the 21st day. Real-time polymerase chain reaction (qRT-PCR) showed that the expression of IL-1β, Interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α) inflammatory factors decreased after the treatment with IL-1ra-loaded thermosensitive hydrogel. Histological evaluation and micro-computed tomography (Micro-CT) showed that IL-1ra-loaded thermosensitive hydrogel could effectively inhibit periodontal inflammation and reduce alveolar bone absorption in rats with diabetic periodontitis. It is worth mentioning that this hydrogel also plays a role in relieving hyperglycemia. Therefore, the temperature-sensitive hydrogel loaded with IL-1ra may be an effective method to treat periodontitis with diabetes. 相似文献
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Zhi He Qiqi Chen Liang He Jinxin Xiong Kuo Gao Bolin Lai Li Zheng Yong Pu Yuanyuan Jiao Zhijun Ma Ziting Tang Mingwang Zhang Deying Yang Taiming Yan 《International journal of molecular sciences》2022,23(18)
Apoptosis plays a key role in the effective removal of excessive and defective germ cells, which is essential for sequential hermaphroditism and sex change in vertebrates. The ricefield eel, Monopterus albus is a protogynous hermaphroditic fish that undergoes a sequential sex change from female to male. Previous studies have demonstrated that apoptosis is involved in sex change in M. albus. However, the apoptotic signaling pathway is unclear. In the current study, we explored the underlying mechanism of apoptosis during gonadal development and focused on the role of the mitochondrial apoptosis signaling pathway in sex change in M. albus. Flow cytometry was performed to detect apoptosis in gonads at five sexual stages and ovary tissues exposed to hydrogen peroxide (H2O2) in vitro. Then the expression patterns of key genes and proteins in the mitochondrial pathway, death receptor pathway and endoplasmic reticulum (ER) pathway were examined. The results showed that the apoptosis rate was significantly increased in the early intersexual stage and then decreased with the natural sex change from female to male. Quantitative real-time PCR revealed that bax, tnfr1, and calpain were mainly expressed in the five stages. ELISA demonstrated that the relative content of cytochrome-c (cyt-c) in the mitochondrial pathway was significantly higher than that of caspase8 and caspase12, with a peak in the early intersexual stage, while the levels of caspase8 and caspase12 peaked in the late intersexual stage. Interestingly, the Pearson’s coefficient between cyt-c and the apoptosis rate was 0.705, which suggests that these factors are closely related during the gonadal development of M. albus. Furthermore, the cyt-c signal was found to be increased in the intersexual stage by immunohistochemistry. After incubation with H2O2, the mRNA expression of mitochondrial pathway molecules such as bax, apaf-1, and caspase3 increased in ovary tissues. In conclusion, the present results suggest that the mitochondrial apoptotic pathway may play a more important role than the other apoptotic pathways in sex change in M. albus. 相似文献
85.
当前校园规划出现了复杂性导向,在校园规划的发展过程中,建筑单体也出现了混合功能的倾向.该文就此倾向进行剖析,并结合广州中医药大学国际楼实际工程提出教育建筑综合体的设计特点. 相似文献
86.
建立电感耦合等离子体质谱(ICP-MS)法测定白酒中Mn和9个毒理性元素含量的分析方法。白酒采用硝酸酸化并加入低浓度盐酸后测定了其中的Be、Cr、Mn、Ni、As、Cd、Sn、Sb、Hg、Pb等元素,盐酸的加入有效地改善了样品溶液中元素的长时间稳定性,尤其是元素Hg和Sn。应用八极杆碰撞/反应池(ORS)技术有效地消除了盐酸的使用所带入的氯离子干扰以及其他质谱干扰,采用基体匹配并通过加入内标溶液有效地补偿样品传输的影响以及溶剂蒸发速率的差异,消除了基体所产生的影响。在选定的工作条件下,方法的线性关系良好,各元素的检出限为0.1312.15 ng/L之间,相对标准偏差(RSD)在0.75%3.48%之间,样品的加标回收率为93.80%110.00%。该方法具有操作简单、快速、结果准确等特点,可用于白酒的质量控制和安全评价。 相似文献
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校园是社会的重要组成部分,也是教书育人、为国家提供发展支撑力量的重要摇篮和基地。通过校园作为驱动社会发展的动力来提高资源的利用效率,缓解能源不足和环境污染等问题,以促进社会的可持续的发展。校园作为公共基础建设的一部分,具有设施多样、人口稠密、能源与资源消耗量大等特点,产生的污染量和能源消耗量非常可观。绿色校园建设受到广泛的关注,本文通过对比国内外的绿色评价体系,并结合《绿色校园评价标准》专注于评分标准适用于用计算机技术的平台,完成了绿色校园评价系统的总体框架设计与构建,讨论了绿色校园评价系统的各子系统的功能,系统的应用将对绿色校园建设起促进作用。 相似文献
89.
以青梅汁为原料,利用酒酒球菌的苹果酸-乳酸发酵(MLF)对青梅汁进行生物降酸的研究。结果表明:接种量为2.0×108CFU/mL,青梅汁的pH≥3.4时,MLF能正常进行,并使样品的酸度降低61.35%以上;接种量为2.6×107CFU/mL时,青梅汁的pH为3.6才能触发MLF,样品的酸度降低了77.60%;接种量为2.3×108CFU/mL,在pH3.6和4.0的青梅汁中,添加1.0g/100g的葡萄糖的样品,与不添加葡萄糖的样品相比,其酸度分别降低了27.04%和34.63%;在柠檬酸-柠檬酸钠缓冲体系中,酒酒球菌使体系酸度降低了26.40%,证实酒酒球菌可利用柠檬酸作为碳源,进行MLF。 相似文献
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