Effect of chronic ethanol treatment on peroxisomal acyl-CoA oxidase activity and lipid peroxidation in rat liver and heart

Summary Chronic ethanol administration was shown to increase catalase and acyl-CoA oxidase activities in rat myocardium but did not alter the activity of liver peroxisomal enzymes. As a result of alcohol consumption a 2–3-fold increase in the level of lipid peroxidation was observed in the heart tissue while in the liver the induction was much less pronounced.     

Thiyl radicals in biosystems: effects on lipid structures and metabolisms

Thiyl radicals are intermediates of enzyme- and radical-driven biochemical processes, and their potential as reactive species in the biological environment has been somehow underestimated. From organic chemistry, however, it is known that thiyl radicals isomerize the double bonds of unsaturated fatty acids to a mixture with very dominating trans isomers. Recently, this reaction has been particularly studied for biosystems, focusing on the effect of thiyl radicals on the natural all-cis double bonds of unsaturated phospholipids, which undergo a conversion to the unnatural trans form. In this paper we report briefly the role of thiyl radicals in biosystems, describe the main features of the radical-induced cis-trans isomerization process under both in vitro and in vivo conditions, and reflect on some consequences for membrane structures, lipid metabolism and enzymatic reactions.Received 29 October 2004; received after revision 3 December 2004; accepted 4 January 2005     

正交试验法优化阿昔洛韦固体纳米粒的处方

采用正交试验法筛选阿昔洛韦固体脂质纳米粒最优处方。利用(W/O/W)复乳-超声法制备阿昔洛韦固体脂质纳米粒,以包封率为评价指标,采用L9(34)正交试验设计筛选出最优处方。单硬脂酸甘油酯用量1.5%、大豆卵磷脂用量0.4%、泊洛沙姆188浓度2%、油相与内水相体积比(Vo/V)i 6。正交试验优化阿昔洛韦固体纳米粒处方有效、可行。     

长期有氧运动对肥胖青少年血糖、血脂及体重的影响

分析长期有氧运动对肥胖青少年血糖、血脂及体重的影响,选择参加某减肥夏令营、不经常锻炼的120个体脂率大于30%的肥胖青少年作为研究对象,受试者进入减肥夏令营后需进行5周全封闭式营养干预与运动干预,所有受试者一周运动6 d,每天上午和下午分别进行2 h的有氧运动,在正式运动前需进行10 min的准备活动,在运动结束后需进行约15 min的整理活动。结果经5周有氧运动后不同性别受试者体重均有所降低,说明长期有氧运动可有效减少肥胖青少年脂肪,降低肥胖青少年体重;肥胖青少年血糖指标均降低,原本异常的受试者血糖水平降低至正常水平,说明长期有氧运动能够有效降低血糖,减少并发糖尿病的危险性;同时,长期有氧运动对改善肥胖青少年血脂水平有明显的效果。     

低强度激光照射对红细胞膜的生物学效应

低强度激光照射对整个血液系统及其主要有形成分红细胞都有着广泛的生物学效应,影响着血液和红细胞的各方面生物物理特性。本文从红细胞膜的角度就低强度激光照射对红细胞膜各组分生物学效应加以讨论。     

不同光照条件下氮浓度对衣藻生长及油脂积累的影响

为探究莱茵衣藻(Chlamydomonas reinhardtii)油脂含量的最佳条件,在不同的光照条件下检测了氮浓度对莱茵衣藻生物量及油脂含量的影响.结果表明:在氮添加和光照强度增加的梯度上,衣藻的油脂含量逐渐降低;光照强度和氮添加量对衣藻的油脂含量都有显著影响;控制光照强度和氮添加量后发现,当光照强度为30μE·m~(-2)·s~(-1),氮质量浓度为100 mg·mL~(-1)时,衣藻油脂含量的质量分数为39.79%,叶绿素质量浓度为17.08 mg·mL~(-1),最适宜衣藻油脂积累.     

抗氧化剂阿魏酸自组装金纳米颗粒的体外抗氧化

对纳米阿魏酸抗氧化剂在巨噬细胞上的抗氧化保护作用进行检测,并采用电子顺磁-自旋捕获技术和光谱法对纳米阿魏酸在细胞水平上清除自由基的能力进行检测.实验结果表明:与抗氧化剂单体相比,纳米阿魏酸抗氧化剂可以更为有效地清除由细胞外界叔丁基过氧化物(t-BuOOH)刺激所产生的活性氧自由基.同时,通过光谱法对细胞膜脂质过氧化物指标丙二醛进行检测,证明纳米抗氧化剂可以更为有效地保护经受外界刺激的巨噬细胞.通过自组装方式可将抗氧化剂纳米化有利于提高抗氧化剂的抗氧化水平.     

马钱子碱固体脂质纳米粒包封率的测定

建立马钱子碱固体脂质纳米粒中药物包封率的测定方法.采用葡聚糖凝胶柱层析法分离马钱子碱固体脂质纳米粒胶体溶液,再用HPLC测定溶液中马钱子碱的质量浓度,计算包封率.该法测定马钱子碱固体脂质纳米粒中马钱子碱的平均包封率为68.13%,RSD值为0.59%.葡聚糖凝胶法简便,准确,可以作为马钱子碱固体脂质纳米粒的包封率测定方法.     

化学发光法研究迷迭香抗脂质过氧化性能

为考察天然抗氧化剂迷迭香的抗脂质过氧化性能,以大豆油为脂质来源,AAPH为自由基引发剂,鲁米诺为发光试剂,构建化学发光体系,并简要探讨体系部分条件的优化.应用优化的化学发光体系,通过与合成抗氧化剂TBHQ的对比,考察抗氧化剂的浓度和反应温度对迷迭香抗脂质过氧化性能的影响;同时通过与国家标准的过氧化值(POV)碘量滴定法的实验结果的对比,考察化学发光法的方法可靠性.实验建立的化学发光体系AAPH的浓度为40 g/L,鲁米诺的浓度为1.0×10-4mol/L,p H为9.此体系下的实验表明迷迭香的抗脂质过氧化性能优于同浓度的TBHQ,且具有热稳定性.化学发光法与碘量滴定法的实验结论一致,表明构建的化学发光体系可靠.