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61.
Previous work from this laboratory has already indicated that capsaicin, stabilizes the rat lung membrane lipid system on long-term treatment. This stabilization of the membrane is further supported by our present findings that capsaicin pretreatment causes significant inhibition of various chemically induced lipid peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes induced by different chemical irritants such as chloroform, dichloromethane, carbon tetrachloride as well as ferrous sulphate. 相似文献
62.
Abstract: Mefloquine was administered in a single dose (1–30 mg/100 g) to rats in order to study its subcellular distribution and effects on rat liver lysosomal structure and function. Subcellular fractionation showed a significant enrichment of mefloquine in lysosomes. Even repeated administration of mefloquine did not affect the levels of cytochrome-P-450 or its reductase, indicating, although not proving, that it is not metabolized by this mono-oxygenase system. Mefloquine caused an expansion of the lysosomal apparatus, earliest seen by 24 h and lasting for some 7 days. Initially, cytoplasmic constituents were seen inside the lysosomes. Later, the lysosomes harboured myelin-like figures (multilamellar bodies) disappearing after 7–10 days. The proteolytic and lipolytic capacity was assessed in isolated lysosomes. Mefloquine caused increased protein degradation but decreased breakdown of lipids. Concomitantly, all five major phospholipids (phosphatidyl-choline, -ethanolamine, -inositol, -serine and sphingomyelin) increased in the lysosomes. It is concluded that: (1) mefloquine is a lysosomotropic drug that accumulates in lysosomes; (2) mefloquine impairs lipid degradation with ensuing accumulation of lipids in lysosomes; and (3) lysosomal trapping explains the high volume distribution of mefloquine. 相似文献
63.
本研究观察到:维生素 E 能抑制 H_2O_2引起的大鼠红细胞脂质过氧化和红细胞溶血,也能抑制分别由维生素 C-NADPH 和 Fe~(2+)-半胱氨酸诱发的大鼠肝、脑微粒体的脂质过氧化,可能还有清除过氧化氢、超氧自由基和羟自由基的作用。 相似文献
64.
65.
观测了急性肝炎和重症肝炎病人血浆VitE及Lpo水平及其动态变化。急性肝炎和重症肝炎病人血浆VitE低于对照组,Lpo高于对照组,均以重症肝炎更明显,且死亡病例血浆VitE低于存活者。部份病人口服VitE不能提高其血浆水平,并随病情加重而逐渐降低。讨论了病毒性肝炎病人血浆VitE降低与Lpo升高的关系及其临床意义,认为动态观测血浆VitE可作为判断重症肝炎病情进展及预后的参考。 相似文献
66.
A critical assessment of allergen component-based in vitro diagnosis in cherry allergy across Europe
A. Reuter J. Lidholm K. Andersson J. Östling M. Lundberg S. Scheurer E. Enrique A. Cistero-Bahima M. San Miguel-Moncin B. K. Ballmer-Weber Stefan Vieths 《Clinical and experimental allergy》2006,36(6):815-823
BACKGROUND: Food allergy to cherry occurs throughout Europe, typically with restricted oral reactions in the central and northern parts but with frequent systemic reactions in the Mediterranean region. Previous studies have demonstrated insufficient sensitivity of commercially available cherry extract reagents in the diagnosis of cherry allergy. OBJECTIVE: To assess the diagnostic performance of specific IgE tests based on recombinant cherry allergens in comparison with an extract-based assay and to skin prick test (SPT). A secondary objective was to analyse the frequency of systemic reactions in cherry-allergic subjects across Europe, including the largest population of LTP-sensitized subjects from central Europe studied to date. METHODS: A total of 186 subjects from central Europe and Spain were studied. Serum IgE was analysed with ImmunoCAP tests carrying rPru av 1, 3 and 4, combined and separately, and cherry extract. RESULTS: Among the central European cherry allergics, the mix of rPru av 1, 3 and 4 had a sensitivity of 95%, compared with 65% for cherry extract, and the IgE binding capacity of the recombinant mix was considerably higher. The sensitivity of the two tests was more comparable in the Spanish population, 95% and 86%, respectively. The recombinant allergen ImmunoCAP equalled SPT in terms of sensitivity and specificity. Consistent with previous reports, major geographic differences in sensitization pattern and prevalence of systemic reactions were found. A significantly higher rate of systemic reactions was found in Spanish patients sensitized to Pru av 3 whereas German patients sensitized to LTP only had oral allergy syndrome. CONCLUSIONS: The recombinant cherry allergen ImmunoCAP is a highly sensitive diagnostic tool, clearly superior to any diagnostic method based on cherry extract. Three cherry allergens are sufficient for detecting sensitization in 95% of cherry-allergic subjects. Systemic reactions are common in LTP-sensitized individuals but seem to require at least one additional causative factor. 相似文献
67.
68.
G. Kostopanagiotou A. Pandazi I. Andreadou A. Doufas I. Chondroudaki T. Kotsis D. Rizos C. Costopanagiotou V. Smyrniotis 《European journal of vascular and endovascular surgery》2005,30(6):648-653
OBJECTIVE: We investigated the dose-related effect of dopexamine and dopamine on free radical production and lipid peroxidation estimated by MDA measurements in an ischaemia-reperfusion model of supraceliac aortic repair. DESIGN: Prospective, randomized, blinded experimental study. MATERIALS: Twenty-five healthy pigs. METHODS: All experiments were performed under general endotracheal anaesthesia. Supraceliac aortic cross clamping was performed in all pigs. The pigs were randomly assigned into five groups (n=5 in each group) and received a continuous intravenous infusion of normal saline (CTL), dopamine 2 microg kg(-1)min(-1) (dopa 2), dopamine 8 microg kg(-1)min(-1) (dopa 8), dopexamine 2 microg kg(-1)min(-1) (dopex 2), dopexamine 8 microg kg(-1)min(-1) (dopex 8). Cardiac output, mean arterial pressure, arterial blood gas analysis and blood sampling for plasma MDA measurements (to reveal lipid peroxidation) were recorded after induction of anaesthesia (baseline), 60 and 120 min after cross-clamping of aorta (ischaemia phase), and 60 and 120 min after restoration of flow (reperfusion phase). RESULTS: Dopexamine and dopamine at 8 microgkg(-1)min(-1) reduced MDA at 60 and 120 min after reperfusion. CONCLUSION: Dopexamine seems superior to dopamine in reducing oxygen free radicals and subsequent lipid peroxidation during reperfusion after supraceliac aortic cross clamping in pigs. 相似文献
69.
实验比较了高脂兔血清(HRS)和正常兔血清(NRS)对培养的人脐静脉内皮细胞(EC)脂质过氧化物(LPO)的形成和EC利用外源性花生四烯酸(AA)合成前列环素(PGI2)能力的影响;同时观察了抗氧化剂VitE对EC的保护作用。结果表明,HRS对EC合成PGI2的影响有一时间和浓度相关的反应过程。用HRS孵育培养呈融合状的EC,在48h前刺激PGI2的产生,48h达最高值,然后急骤下降;而LPO含量随着孵育时间的延长呈直线上升(r=0.987)。随着HRS浓度的增加,LPO含量逐渐升高,EC合成PGI2能力呈下降趋势。VitE可阻止HRS引起的EC中LPO含量的增加和PGI2合成能力的下降。 相似文献
70.
猕猴桃中药复方制剂对血清SOD及MDA含量的影响 总被引:4,自引:0,他引:4
猕猴桃中药复方制剂系采用猕猴桃汁为基质,配加绞股蓝、丹参等中药的有效成分制成。为了研究它的保健作用,在63例50岁以上、无急性疾病的中、老年人,36例30~49岁健康的青年,32例14~17岁健康的少年中进行试验,10ml每日2次连续服用30天后,中老年人血液SOD显著增高,70岁以上老人平均增高2.8倍,血清MDA明显下降,70岁以上平均下降87.5%。 相似文献