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41.
Nerolidol Protects Against LPS‐induced Acute Kidney Injury via Inhibiting TLR4/NF‐κB Signaling 下载免费PDF全文
Lu Zhang Dandan Sun Yan Bao Yan Shi Yan Cui Minghao Guo 《Phytotherapy research : PTR》2017,31(3):459-465
Acute kidney injury (AKI) is a critical care syndrome, resulting in acute reduction of renal function and up to 22% mortality of hospitalized patients. Nerolidol is a major component in several essential oils that possesses various pharmacological properties. The present study aimed to investigate the potential effect of nerolidol on lipopolysaccharide (LPS)‐induced AKI. Nerolidol dose‐dependently reduced the pathological injuries of kidney induced by LPS in rats. Nerolidol significantly decreased the levels of blood urea nitrogen and creatinine in LPS‐treated rats in a dose‐dependent manner. In addition, nerolidol inhibited LPS‐induced decrease of cell viability in NRK‐52E rat proximal tubular cells, which effect was concentration dependent. Nerolidol notably inhibited the increase of TNFα and IL‐1β in LPS‐treated rats and the mRNA expression of TNFα and IL‐1β in LPS‐treated NRK‐52E cells. Nerolidol suppressed the increase of toll‐like receptor 4 (TLR4) expression, phosphorylation and nuclear translocation of p65 NF‐κB in kidneys of LPS‐treated rats and LPS‐treated NRK‐52E cells. Overexpression of TLR4 and p65 NF‐κB significantly suppressed nerolidol‐induced inhibition of TNFα and IL‐1β expression and increase of cell viability in LPS‐treated cells. In summary, we found that nerolidol played a critical anti‐inflammatory effects through inhibition of TLR4/NF‐κB signaling and protected against LPS‐induced AKI. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
42.
Junyou Yang Wen Zhu Xianhui Gao Siqian Bao Xian Fan 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,577(1):117-123
A Bi2Te3 VA–VIA group compound thin film was prepared via the route of electrochemical atomic layer epitaxy in this paper. The dependence of thin film formation on the electrochemical conditions (such as deposition potential control, supporting electrolyte and substrate) was studied, and the formation process of Bi2Te3 film was determined. The results show that Bi upd on Pt occurs at more negative potential in a HNO3 supporting electrolyte than in a HClO4 supporting electrolyte, and the Te upd peak moves to a more negative potential in HClO4 supporting electrolyte solution than that in HNO3 solution; Both Te and Bi upd on an Ag substrate occur at more negative potentials than that on a Pt substrate. In order to reach steady state deposition, a potential adjustment is necessary for the first 30 or more cycles of each component. After deposition of this initial ‘buffer layer’, the potentials can be kept constant for the remaining cycles. The effect of the slope of the shift of potential used to deposit the first 30 atomic layers of Bi and Te on the deposit has also been investigated. The deposit exhibits a two phase mixture of excess elemental Bi and Bi2Te3 compound when the slope is larger than ?4 mV/p (p indicates per cycle); a single-phase Bi2Te3 compound was obtained at a slope of ?6 mV/p, and Bi4Te3 compound also appears in the deposit along with Bi2Te3 when the slope is decreased to a more negative value of ?10 mV/p. 相似文献
43.
经牙槽嵴顶入路的上颌窦提升植骨及同期种植体植入术 总被引:5,自引:0,他引:5
目的 减轻传统的上颌窦提升术给患者增加的手术创伤,简化上颌窦提升牙种植的手术步骤。方法 应用Frialit-2骨挤压器对11例患者(14个牙位)行经牙槽嵴顶入路的上颌窦提升、植、骨即刻牙种植术,术后随访时间平均15个月(10~21个月)。结果 11例(14颗种植体)未发现鼻出血、上颌窦炎症反应及种植体松动、脱落,X线检查种植体周围无阴影,已形成良好的骨结合。结论 应用Frialit-2骨挤压器行经牙槽嵴顶入路的上颌窦提升牙种植术是一种创伤小、操作简单、行之有效的上颌后部牙种植外科技术。 相似文献
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46.
NIU Pei Hua ZHAO Xiang LU Rou Jian ZHAO Li HUANG Bao Ying YE Fei WANG Da Yan TAN Wen Jie 《Biomedical and environmental sciences : BES》2021,34(9):725-728
The new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is spreading worldwide with the number of confirmed cases increasing dramatically[1,2]. Coronaviruses have the largest genome among RNA viruses and have caused two major outbreaks[3,4]. The new coronavirus (SARS-CoV-2) is the third coronavirus spread globally in the past 17 years. According to the World Health Organization, SARS-CoV-2 has affected more than 155.6 millon patients in 222 countries as of 6 May 2021 and has become a major global health concern (https://www.who.int/emergencies/diseases/novel-coronavirus-2019). 相似文献
47.
目的 探索不同浓度星孢菌素对山羊颞下颌关节盘细胞自组装基体收缩性及细胞外基质合成的影响。方法 单层培养山羊颞下颌关节盘细胞至P3代,将5.5×10 6个细胞在不同浓度(0、0.1、1、10、100 nmol·L -1)星孢菌素的完全培养基中分别接种于三维柱状琼脂糖井;每天每井换液,培养1周后观察自组装基体的形态变化;冰冻切片染色显示自组装基体细胞外基质及α-平滑肌动蛋白(α-SMA)的分布;酶联免疫吸附测定(ELISA)和Blyscan试剂盒检测基体细胞外基质含量的变化。结果 山羊颞下颌关节盘细胞接种4 h后,星孢菌素组和对照组细胞均在琼脂糖井内自组装,形成一圆盘状基体,之后变成球形。各组自组装基体在1周时天狼星红染色可见基体内大量胶原纤维分布;番红染色显示基体内纤维软骨样细胞明显分泌糖胺多糖(GAGs);Ⅰ型胶原(ColⅠ)在免疫组织化学染色中呈强阳性;α-SMA免疫组织化学染色为弱阳性。星孢菌素组自组装基体内ColⅠ和GAGs较高,其中10 nmol·L -1组最明显(P<0.01)。结论 星孢菌素对自组装基体的收缩有一定干预效果,但不是非常突出;它更有利于细胞外基质的合成。 相似文献
48.
目的 了解胰岛素样生长因子-I(IGF-I)在三维培养条件下对人牙周膜细胞(hPDLCs)增殖及碱性磷酸酶(ALP)活性的影响.方法 通过组织块法分离培养hPDLCs.采用旋转细胞培养系统(RCCS)建立三维培养环境.将细胞分为4组,分别为阴性对照组、阳性对照组(三维培养组、IGF-I组)、实验组(三维培养加IGF-I... 相似文献
49.
弯制卡环与铸造卡环对龈下微生物的影响 总被引:1,自引:0,他引:1
目的了解卡环戴入前后基牙龈下微生物变化,考察弯制卡环与铸造卡环对龈下微生物影响的差异.方法检查戴牙前、戴牙后1周、1月和3月,弯制卡环和铸造卡环所在基牙龈下可培养细菌总量及革兰氏阴性菌构成比的变化.结果与戴牙前相比,戴牙后1周、1月和3月龈下可培养细菌总量及革兰氏阴性菌构成比均明显增加,差异有统计学意义(P<0.05),戴牙后1月,弯制卡环与铸造卡环所在基牙龈下革兰氏阴性菌构成比有统计学差异(P<0.05).结论在本文观察期(3个月)内,卡环的戴入造成龈下微生物中革兰氏阴性菌构成比显著增加,弯制卡环与铸造卡环对龈下微生物中革兰氏阴性菌构成比的影响没有显著差异. 相似文献
50.
Nonalcoholic fatty liver disease (NAFLD) is a prevalent long-term disease in the world. Liquiritigenin (LQ) is protective against a variety of hepatotoxins. Herein, we report the potential mechanism of LQ on a high-fat diet (HFD) induced NAFLD. NAFLD mice model was established by HFD for 12 weeks, and LQ treatment for 1 week. Commercially available assay kits measure liver triglycerides (TG) and total cholesterol (TC) levels. Plasm TC, TG, high-density-lipoprotein (HDL-C), and low-density-lipoprotein cholesterol (LDL-C) levels were also monitored by biochemistry. Enzyme linked immunosorbent assay (ELISA) kits were performed to analyze the pro-inflammatory factors, and intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (IPITT), and serum insulin were also determined. GO and KEGG pathway enrichment analysis was employed to analyze the overlapping genes of LQ targets and NAFLD development-related targets. Western blot was performed on key proteins of the enriched signaling pathway. HFD mice showed significant increases in hepatic TG and TC, and plasm TC, TG, and LDL-C in blood lipids, while HDL-C significantly decreased, and LQ treatment reversed their levels (p < 0.05). LQ also alleviated HFD-induced elevated levels of IPGTT, IPITT, and homeostasis model assessment of insulin resistance (HOMA-IR). And serum levels of the pro-inflammatory factor were also suppressed by LQ. PI3K/AKT pathway was enriched by KEGG pathway enrichment, and its key proteins p-PI3K and p-AKT were elevated after LQ treatment (p < 0.05). We found for the first time that LQ improves lipid accumulation, alleviates insulin resistance, and suppresses inflammatory responses in NAFLD mice, which might be associated with the activation of the PI3K/AKT pathway. 相似文献