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1.
Microbeads and fragments have been widely studied, while glitter remains neglected by the literature although found in a variety product (e.g., body paints, nail polish, cosmetics, craft products). The main aim of this study was to assess the effects of different types and concentrations of glitter particles on Mytilus galloprovincialis after 7 days of exposure. The experiment was divided into a preliminary test and a confirmatory test. Our findings support the hypothesis for a link between concentration and type of glitter particles, percentage of recovery and oxidative stress in M. galloprovincialis. There was a significant correlation between particle length and percentage of particles recovered in water, suggesting that the digestive tract of M. galloprovincialis retains smaller particles more. In addition, we noted an increase in antioxidant defense induced by smaller particles. Moreover, certain types of glitter crumbled and shortened in length, resulting in higher levels of oxidative stress biomarkers. Finally, the star-shaped glitter particles had a different effect on oxidative stress biomarkers. Further studies are needed to clarify the toxic effects of glitter on aquatic organisms and to quantify its proportion to other microplastics in the environment. 相似文献
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【摘要】 目的 探讨腹腔镜下胃穿孔修补术对老年胃穿孔患者氧化应激及胃泌素水平的影响。方法 选取2019年8月至2020年12月淮滨县人民医院收治的75例老年胃穿孔患者作为研究对象,根据不同治疗方法将其分为腹腔镜组(40例) 和开腹组 (35例), 腹腔镜组患者采用腹腔镜下胃穿孔修补术治疗,开腹组患者采用开腹胃穿孔修补术治疗, 对比观察两组患者手术时间、术中出血量、肠鸣音恢复时间、肛门排气时间、住院时间及 氧化应激水平、胃泌素水平与疼痛程度变化情况。结果 腹腔镜组患者手术时间明显长于开腹组,术中出血量明显少于开腹组,肠鸣音恢复时间、肛门排气时间、住院时间均明显短于开腹组(t = 5.628、5.655、5.474、5.177、7.267,P 均 < 0.001);术后1、24 h,腹腔镜组患者丙二醛(MDA)、超氧化物歧化酶(SOD)水平均明显低于开腹组(术后1 h: t=4.037、2.974,P<0.001、P=0.004;术后24 h:t=5.721、2.950,P < 0.001、P = 0.004);术后 1、24、48、72 h,腹腔镜组患者胃泌素水平均明显高于开腹组 ( t = 2.897、2.703、3.583、3.393,P = 0.005、P = 0.009、P <0.001、P <0.001);术后 1、3 d, 腹腔镜组患者视觉模拟评分法(VAS)评分均明显低于开腹组 (t = 2.437、2.686,P = 0.017、0.009)。结论 采用腹腔镜下胃穿孔修补术治疗老年胃穿孔, 可降低患者术后机体氧化应激反应, 提高胃泌素水平, 减轻疼痛, 缩短住院时间, 临床应用价值较高。 相似文献
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目的探讨醋延胡索炮制前后HPLC指纹图谱与镇痛药效的相关性,筛选炮制特征成分。方法建立生延胡索与醋延胡索HPLC指纹图谱,对两者化学成分进行差异性分析,以大鼠扭体反应为模型建立评价指标,采用超氧化物歧化酶(superoxide dismutase,SOD)、丙二醛、孕酮、雌二醇、前列腺素E_2(prostaglandin E_2,PGE_2)、前列腺素F_(2a)(prostaglandin F_(2a),PGF_(2a))等指标评价镇痛药效,结合灰色关联度分析法与熵权法研究醋延胡索的谱-效关系,指认醋延胡索炮制特征成分。结果建立了不同批次生延胡索饮片、醋延胡索饮片的HPLC指纹图谱,确定了31个共有峰。生延胡索饮片与醋延胡索饮片均有止痛效果,以醋延胡索止痛效果最为显著。镇痛谱效关联度分析得到峰9、18~21、25、26醋炙后关联度得分有了显著的提升,与醋炙后镇痛疗效呈显著正相关。结论通过谱-效关系明确了醋延胡索炮制特征成分为原阿片碱、盐酸巴马汀、盐酸小檗碱、去氢紫堇碱、延胡索乙素、四氢小檗碱、延胡索甲素,为醋延胡索炮制质量控制提供一定依据。 相似文献
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《Saudi Pharmaceutical Journal》2022,30(11):1665-1671
5-fluorouracil (5FU) is widely used to treat colorectal cancer (CC) and its main mechanisms of anticancer action are through generation of ROS which often result in inflammation. Here, we test the effect of Lycopene against 5FU in Caco2 cell line. Caco2 cells were exposed to 3 µg/ml of 5FU alone or with 60, 90, 120 µg/ml of lycopene. This was followed by assessment of cytotoxicity, oxidative stress, and gene expression of inflammatory genes. Our findings showed that Lycopene and 5FU co-exposure induced dose-dependent cytotoxic effect without compromising the membrane integrity based on the LDH assay. Lycopene also significantly enhanced 5FU-induced SOD activity and GSH level compared to control for all mixture concentrations (p < 0.01). Lycopene alone and combination with 5FU-induced expression of IL-1β, TNF-α, and IL-6. Furthermore, IFN-γ expression was significantly enhanced by only mixture of lycopene (90 µg/ml) and 5FU (p < 0.05). In conclusion, Lycopene supplementation with 5FU therapy resulted in improvement in antioxidant parameters such as catalase and GSH levels giving the cell capacity to cope with 5FU-mediated oxidative stress. Lycopene also enhanced IFN-γ expression in the presence of 5FU, which may activate antitumor effects further enhancing the cancer killing effect of 5FU. 相似文献
6.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
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目的克隆表达、纯化金黄色葡萄球菌(Staphylococcus aureus)锰超氧化物歧化酶(Mn-SOD)并测定其活性。方法使用Clustal Omega比对不同来源Mn-SOD的序列,使用Swiss model网站预测金黄色葡萄球菌Mn-SOD的三级结构。提取细菌DNA,以此为模板PCR扩增获得Mn-SOD基因并将其与pET28a连接,构建pET28a-Mn-SOD重组质粒。将重组质粒转化大肠埃希菌BL21(DE3)获得重组菌BL/pET28a-Mn-SOD,使用IPTG诱导表达重组Mn-SOD,通过镍柱亲和层析纯化Mn-SOD蛋白并测定不同pH条件下的酶活性。结果金黄色葡萄球菌Mn-SOD具有Mn-SOD的特征序列和锰离子结合位点。成功得到重组质粒pET28a-Mn-SOD,转化大肠埃希菌BL21后表达相对分子质量为24.8×10^3的Mn-SOD,使用Ni^2+柱纯化后得到高纯度的Mn-SOD,且在pH值为7.5时活性较高,约为3 200 U/mL。结论成功构建了pET28a-Mn-SOD重组质粒能,表达的Mn-SOD重组蛋白纯化后仍具有SOD活性。 相似文献