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??Objective    To observe the effects of lithium chloride pretreatment on cognitive ability of aged rats after oral and maxillofacial surgery. Methods    A total of 48 aged male SD rats??18 ~ 20 months old??weight 550 ~ 700 g?? were bought from the Experimental Animal Center of China Medical University . These rats were randomly divided into three groups??including the normal control group??group C??n=16????surgery and anesthesia group??group O??n=16????and lithium chloride preconditioning group??group L??n=16??.Rats in each group were randomly divided into two parts??one part was given Morris water maze test three days after the surgery and its characteristics of behavior tested. Another part was decapitated 24 h after the surgery and extracted and the hippocampus brain separated at the same time. Test expression content of IL-1β GSK-3β p-GSK-3β??ser9??in the hippocampus by Elisa and Western blotting detection method respectively. Results    Morris water maze test showed that??the first day after surgery??latencies of group L and O were significantly longer than group C??compared with group C in swimming distance?? latency and swim distances of group L were shorter than group O. With the comparison of multiple analysis of variance??differences were statistically significant??P??0.05??. Groups L and O in the second day were slightly shortened compared to the first day??on the third day after surgery it has also improved over the second day. Space exploration experiments in rats showed that??the dwell time of group C was significantly longer in the platform quadrant and the frequency of crossing the platform also increased compared with groups L and O. In addition??group L and group O were higher in IL-β levels than group C??the difference being statistically significant by analysis of variance??P??0.05????but group L was significantly lower compared with group O??the difference being statistically significant??P??0.05??. The content of GSK-3β of three groups were of no significant difference??P > 0.05????but p-GSK-3β??ser9??content was significantly lower in group L and O than in group C. The content of GSK-3β of group L was higher than in group O??the difference being statistically significant??P??0.05??. Conclusion    Pretreatment with lithium chloride in postoperative aged rats can inhibit the expression of inflammatory cytokines and increase GSK-3β phosphorylation in the hippocampus cells??so p-GSK-3β??ser9??upregulates and inhibites  the apoptosis of brain cells??thereby improved cognitive abilities after the cavity and maxillofacial surgery.  相似文献   
13.
In this article, construction of amperometric sensor(s) based on screen-printed carbon electrodes covered by thin layers of two types of carbon nanomaterials serving as amplifiers, and containing [Cu(bipy)2Cl]Cl∙5H2O complex is reported. Their performance and biomimetic activity towards two selected neurotransmitters (dopamine and serotonin) was studied mainly using flow injection analysis (FIA). The important parameters of FIA such as working potential, flow rate, and pH were optimized. The mechanism of the catalytic activity is explained and experimentally confirmed. It reveals that presence of hydrogen peroxide plays a crucial role which leads to answer the title question: can presented complex really be considered as a tyrosinase biomimetic catalyst or only as a redox mediator?  相似文献   
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Objectives: Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive pathological changes of the brain. A number of studies demonstrated compelling evidence of the importance of oxidative processes in AD pathogenesis. Raisin contains polyphenol, phenolic acid, and tannin compounds, which have antioxidant and anti-inflammatory properties. The present study was aimed to evaluate the protective effect of raisin on neurobehavioral and histological changes in rats with Alzheimer.

Methods: Animal model of AD was induced by intraperitoneal injection of aluminium chloride for 60 days (100?mg/kg body weight). During these 60 days both Alzheimer’s and control rats were given 6?g of raisin per rat. At the end of the treatment, blood was collected for biochemical assessment. We used a Morris water task and passive avoidance test to assess spatial memory.

Results: Our results showed that aluminium exposure significantly decreased the memory in the MWT and passive avoidance test, but in the raisin?+?AlCl3 group, it significantly increased spatial memory in both tests. Also, Aluminium exposure significantly increased malondialdehyde (MDA) and decreased ferric reducing ability of plasma (ferric reducing/antioxidant power (FRAP)), while treatment with raisin significantly decreased MDA and increased FRAP in plasma of blood.

Discussion: Our findings showed that raisin has a neuroprotective effect and improves the spatial memory in AD animal models.  相似文献   

16.
《Molecular therapy》2021,29(10):3072-3092
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17.
Vinyl chloride (VC) is a common industrial organic chlorine and environmental pollutant. In recent years, the dietary structure of residents especially Chinese has gradually shifted to western dietary patterns. VC aggravates dietary fatty acid-induced hepatic steatosis, but its mechanism is still unclear. And if the risk factors for steatosis persist, more severe diseases such as fibrosis and cirrhosis will occur. Therefore, we studied the effects and mechanisms of VC (160 and 800 mg/m3) and its metabolite (chloroacetaldehyde, 2.25, 4.5, and 9 μM) on hepatic steatosis of high-fat diet (HFD)-fed mice and palmitic acid (PA, 100 μM) treated HepG2 cells. Liver and serum biochemical indicators and pathological staining of the liver showed that the hepatic steatosis of VC combined with HFD groups was more severe than that of single-exposure groups (HFD group, low-dose VC group, and high-dose VC group). Moreover, VC enhanced HFD-induced oxidative stress (OS) and endoplasmic reticulum stress (ERS) and further upregulated the expression of sterol regulatory element-binding protein 1 (SREBP-1) and FAS. Besides, antioxidants and ERS inhibitors reduced the steatosis of HepG2 cells induced by VC metabolites and PA. These results suggest that VC exposure can enhance the degree of hepatic steatosis in HFD-fed mice. VC combined with HFD led to OS and ERS and upregulated the expression of de novo lipogenesis-related proteins, which may be related to the occurrence of hepatic steatosis. And the increased expression of CYP2E1 induced by VC combined with HFD may be the cause of OS.  相似文献   
18.
摘要 目的:建立普拉洛芬滴眼液中苯扎氯铵含量的HPLC测定方法。方法:用十八烷基硅烷键合硅胶为填充剂,以0.07mol?L乙酸铵溶液(含三乙胺1%,冰醋酸调节pH至5.0)-乙腈(25:75)为流动相,检测波长为210nm。结果:在选定的色谱条件下,各组分分离度良好,苄基十二烷基二甲基氯化铵、苄基十四烷基二甲基氯化铵分别在3.4~33.8μg?mL-1,0.7~5.5μg?mL-1的浓度范围内线性关系良好(r>0.999);精密度试验的RSD分别为0.2%和0.7%、稳定性试验的RSD均不大于1.0%;回收率分别为99.9%,101.2%(n=9,RSD<1.0%)。C12与C14的检出限分别为3.4 ng?mL-1和110.5 ng?mL-1。在测定3批样品中,其中C12含量(μg?mL-1)分别为57.195,57.009,56.830;C14含量(μg?mL-1)分别为12.850,12.714,12.937;苯扎氯铵含量(μg?mL-1)分别为70.045,69.723,69.767。结论:本方法专属性强,准确度高,重现性好,能分别控制普拉洛芬滴眼液中苯扎氯铵两种同系物的含量。  相似文献   
19.
摘 要 目的:建立GC-MS法测定三层共挤输液用袋中苯乙烯单体在氧氟沙星氯化钠注射液中迁移量的方法。方法: 采用GC-MS法测定氧氟沙星氯化钠注射液中苯乙烯单体含量,从而考察氧氟沙星氯化钠注射液的包装袋(三层共挤输液用袋)中苯乙烯在药液中的迁移量,色谱柱为DB 624 123 1334毛细管柱(30 m×0.32 mm,1.8 μm),柱温采用程序升温,顶空自动进样,由电子轰击源(EI)选择离子监测(SIM)模式进行检测。结果:苯乙烯在46.96~543.60 ng·mL-1(r=0.999 9)浓度范围内具有良好线性关系;平均回收率为101.2%,RSD为3.1%(n=9)。结论:本方法简便、准确、重复性好,可用于该药品与包装的相容性评价。  相似文献   
20.
目的 建立同时测定盐酸洛美沙星滴眼液中5种抑菌剂(羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵和苯扎氯铵)的HPLC方法。方法 采用Extend C18(4.6mm×250mm, 5μm)色谱柱,流动相为1%三乙胺溶液(磷酸调pH值至3.0)-甲醇,梯度洗脱,流速为1.0mL/min,柱温35℃,检测波长为262nm。结果 羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵/苯扎氯铵各峰均分离良好;羟苯甲酯在0.0410~0.8204mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.2%(RSD=0.8%, n=9);羟苯乙酯在0.0400~0.7996mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.3%(RSD=0.7%, n=9);硫柳汞在0.0806~1.6112mg/mL范围内线性关系良好(r=0.9995),平均回收率为100.8%(RSD=0.9%, n=9);苯扎溴铵在0.0204~0.4076mg/mL范围内线性关系良好(r=0.9998),平均回收率为100.0%(RSD=0.9%, n=9);苯扎氯铵0.0197~0.3932mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.4%(RSD=1.0%, n=9)。结论 该方法准确、灵敏、简便,可用于盐酸洛美沙星滴眼液中羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵及苯扎氯铵5种抑菌剂的检查。  相似文献   
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