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81.
Vitamin D (VD) is a major regulator of calcium metabolism in many living organisms. In addition, VD plays a key role in regulating innate and adaptive immunity in vertebrates. Neutrophils constitute an important part of the first line of defense against invading microbes; however, the potential effect of VD on neutrophils remains elusive. Thus, in this study zebrafish in different developmental stages were utilized to identify the potential role of VD in the basal homeostasis and functions of neutrophils. Our results showed that addition of exogenous VD<sub>3</sub> promoted granulopoiesis in zebrafish larvae. Reciprocally, neutrophil abundance in the intestine of adult zebrafish with a cyp2r1 mutant, lacking the capacity to 25-hydroxylate VD, was reduced. Moreover, VD-mediated granulopoiesis was still observed in gnotobiotic zebrafish larvae, indicating that VD regulates neutrophil generation independent of the microbiota during early development. In contrast, VD was incapable to influence granulopoiesis in adult zebrafish when the commensal bacteria were depleted by antibiotic treatment, suggesting that VD might modulate neutrophil activity via different mechanisms depending on the developmental stage. In addition, we found that VD<sub>3</sub> augmented the expression of il-8 and neutrophil recruitment to the site of caudal fin amputation. Finally, VD<sub>3</sub> treatment significantly decreased bacterial counts and mortality in zebrafish infected with Edwardsiella tarda (E. tarda) in a neutrophil-dependent manner. Combined, these findings demonstrate that VD regulates granulopoiesis and neutrophil function in zebrafish immunity.  相似文献   
82.
Aims dl‐PHPB (potassium 2‐(1‐hydroxypentyl)‐benzoate) has been shown to have neuroprotective effects against acute cerebral ischemia, vascular dementia, and Alzheimer''s disease. The aim of this study was to investigate the effects of dl‐PHPB on memory deficits and preliminarily explore the underlying molecular mechanism.MethodsBlood glucose and behavioral performance were evaluated in the KK‐Ay diabetic mouse model before and after dl‐PHPB administration. Two‐dimensional difference gel electrophoresis (2D‐DIGE)‐based proteomics was used to identify differentially expressed proteins in brain tissue. Western blotting was used to study the molecular mechanism of the related signaling pathways.ResultsThree‐month‐old KK‐Ay mice were given 150 mg/kg dl‐PHPB by oral gavage for 2 months, which produced no effect on the level of serum glucose. In the Morris water maze test, KK‐Ay mice treated with dl‐PHPB showed significant improvements in spatial learning and memory deficits compared with vehicle‐treated KK‐Ay mice. Additionally, we performed 2D‐DIGE to compare brain proteomes of 5‐month KK‐Ay mice treated with and without dl‐PHPB. We found 14 altered proteins in the cortex and 11 in the hippocampus; two of the 25 altered proteins and another four proteins that were identified in a previous study on KK‐Ay mice were then validated by western blot to further confirm whether dl‐PHPB can reverse the expression levels of these proteins. The phosphoinositide 3‐kinase/protein kinase B/glycogen synthase kinase‐3β (PI3K/Akt/GSK‐3β) signaling pathway was also changed in KK‐Ay mice and dl‐PHPB treatment could reverse it.ConclusionsThese results indicate that dl‐PHPB may play a potential role in diabetes‐associated cognitive impairment through PI3K/Akt/GSK‐3β signaling pathway and the differentially expressed proteins may become putative therapeutic targets.  相似文献   
83.
An acoustic metamaterial absorber of parallel–connection square Helmholtz resonators is proposed in this study, and its sound absorption coefficients are optimized to reduce the noise for the given conditions in the factory. A two–dimensional equivalent simulation model is built to obtain the initial value of parameters and a three–dimensional finite element model is constructed to simulate the sound absorption performance of the metamaterial cell, which aims to improve the research efficiency. The optimal parameters of metamaterial cells are obtained through the particle swarm optimization algorithm, and its effectiveness and accuracy are validated through preparing the experimental sample using 3D printing and measuring the sound absorption coefficient by the standing wave tube detection. The consistency between the experimental data and simulation data verifies feasibility of the proposed optimization method and usefulness of the developed acoustic metamaterial absorber, and the desired sound absorption performances for given conditions are achieved. The experimental results prove that parallel–connection square Helmholtz resonators can achieve an adjustable frequency spectrum for the low frequency noise control by parameter optimization, which is propitious to promote its application in reducing the noise in the factory.  相似文献   
84.
成人下颌偏斜患者颞下颌关节形态及位置的变化   总被引:1,自引:1,他引:0  
目的:研究下颌偏斜患者颞下颌关节形态及其位置的变化.方法:对21例下颌偏斜患者和20例个别理想[牙合]志愿者拍摄颞下颌关节中位断层片,选择描述髁突位置及髁突和关节窝形态的15个指标进行测量及统计分析.结果:下颌偏斜患者双侧关节结节高度、关节窝指数增大,髁突后斜面与水平基准线的夹角减小;偏斜侧的关节前间隙、关节前后间隙面积比,髁突高度、髁突上部高度减小;对侧的关节上间隙、髁突高度、髁突上部高度、髁突前斜面与水平基准线的夹角、关节窝后斜面与水平基准线的夹角增大.结论:下颌偏斜患者的双侧髁突和关节窝形态及髁突在关节窝中的位置都发生了改变,尤其以非偏斜侧髁突变化较为明显.  相似文献   
85.
目的:通过对大鼠骨髓基质干细胞成脂肪分化过程中雌激素受体β表达规律的研究,进一步明确雌激素受体β与骨代谢的相关性。方法:大鼠骨髓基质干细胞培养,成骨诱导分化,钙染色。成脂肪诱导分化,油红O染色。Western blot方法测定大鼠骨髓基质干细胞成脂肪分化过程中雌激素受体β的表达。结果:全骨髓贴壁方法培养获得大鼠骨髓基质干细胞。成脂诱导分化显微镜下脂肪滴、油红O染色阳性细胞随成脂肪时间增加而增多。雌激素受体β的表达随成脂时间的增加而递增。结论:大鼠骨髓基质干细胞成脂肪分化过程中ERβ的表达随时间逐渐增加。  相似文献   
86.
综述近10余年来火针配合拔罐的临床应用概况。火针配合拔罐在皮肤科、骨伤科及外科得到了广泛的应用。今后可进一步提高其临床科研的设计水平,以充分体现火针配合拔罐的优势。  相似文献   
87.
中药方剂防治骨质疏松症的研究概况   总被引:1,自引:5,他引:1  
中药方剂具有疗效好、副作用小、作用全面、适合长期服用等优势,已广泛应用于骨质疏松的防治。经典方来源于古代医书记载,疗效确切,临床上通过辨证施治,可随证对处方进行加减化裁;经验方来源于医师多年临床经验,处方组成相对固定,各自具有自身的特点,适用于特定证候类型的骨质疏松症;中成药的处方、剂型固定,服用方便,可单独使用,或与化学药物配伍使用。中药方剂防治骨质疏松症具有独特的优势,但尚有许多不足,应从整体、器官、组织、细胞和分子水平上系统研究其作用机制和特点。  相似文献   
88.
大黄素、小檗碱对HepG2细胞胰岛素抵抗的预防作用研究   总被引:1,自引:0,他引:1  
目的:研究大黄素、小檗碱对HepG2细胞产生胰岛素抵抗的预防作用及机制。方法:首先用MTT法筛选大黄素、小檗碱作用于HepG2细胞的实验浓度,然后用软脂酸诱导HepG2细胞,同时分别加入大黄素、小檗碱干预,并设正常组、对照组进行比较,通过葡萄糖氧化酶法、蒽酮法、RT-PCR法,观察大黄素、小檗碱对HepG2细胞上糖代谢及瘦素长型受体、短型受体mRNA表达水平的影响。结果:对照组成为具有胰岛素抵抗的HepG2细胞,且细胞上瘦素长型及短型受体mRNA的表达水平较正常纽显著下降(P〈0.01);而大黄素、小檗碱组培养液中葡萄糖含量、细胞内糖原含量以及细胞上瘦素长型及短型受体mRNA的表达水平较正常组无明显改变(P〉0.05)。结论:大黄素、小檗碱均能预防HepG2细胞产生胰岛素抵抗,这一作用与它们影响HepG2细胞上糖代谢及瘦素受体mRNA表达水平有关。  相似文献   
89.
目的:探讨芍甘多苷对CCl4,亚急性肝损伤大鼠血清转氨酶、肝脏病理及肝细胞线粒体保护作用.方法:采用CCl4,诱发大鼠亚急性肝损伤,然后灌胃给予不同剂量的芍甘多苷治疗,观察药物对血清ALT,AST,肝脏组织病理,肝细胞线粒体超微结构和ATPase,MDA,SOD的影响.结果:芍甘多苷对CCl4诱发大鼠亚急性肝损伤升高的转氨酶有明显的降低作用,并使形态学上的肝细胞变性和坏死得到明显改善和恢复,能提高线粒体Na+-K+-ATPase,Ca2+-ATPase活性,降低线粒体MDA含量,升高SOD活性,改善线粒体超微病理变化,降低肝细胞线粒体截面面积、周长、等效直径、平均吸光度.结论:芍甘多苷有明显的肝脏保护作用,其机制与减轻线粒体损伤有关.  相似文献   
90.
Casticin, a compound purified from the Chinese herb Viticis Fructus, has been proven effective in preventing tumor progression in previous studies. Ulcerative colitis (UC) is a common inflammatory bowel disease that affects millions of people worldwide, but no effective and safe drugs are available. In this study, we aimed to study how did casticin affect UC by evaluating its effects on dextran sulfate sodium (DSS)‐induced colitis in mice. Our data suggested that casticin attenuated body weight loss, colon length shortening, and pathological damage in the colon of DSS‐treated mice. Casticin decreased reactive oxygen species level and chemocytokines (IL‐1β, IL‐6, TNF‐α) productions in colon tissue. The decreased reactive oxygen species level and suppressed proinflammatory cytokines productions were also confirmed in casticin‐treated LPS‐stimulated RAW264.7 cells and hydrogen peroxide‐treated CACO‐2 cells in vitro. Mechanistically, casticin treatment prevented the profound activation of AKT signaling caused by DSS administration. And casticin inhibited the productions of proinflammatory chemocytokines through downregulating AKT/NF‐κB pathway in macrophages. Meanwhile, data revealed that casticin increased expressions of endogenous antioxidants peroxiredoxin 3 and MnSOD were through activation in FOXO3α signaling by downregulating AKT signaling in colon epithelium cells. Our findings demonstrated that casticin alleviated DSS‐induced UC by increasing the antioxidant enzyme peroxiredoxin 3 and MnSOD expressions, and decreasing the production of proinflammatory chemocytokines through inhibition of AKT signaling.  相似文献   
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