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仙茅苷对自由基的清除作用 总被引:5,自引:0,他引:5
目的研究仙茅(Curculigo orchioidesGaertn.)主要成分仙茅苷(curcu ligoside)对羟自由基和超氧阴离子自由基的清除作用。方法分别采用比色法及电子顺磁共振技术(ESR)测定仙茅苷对羟自由基和超氧阴离子自由基的清除效果。结果仙茅苷对羟自由基和超氧阴离子自由基均有良好的清除作用,其清除率略低于茶多酚。结论仙茅苷对自由基具有明显的清除作用,是一种有效的天然抗氧化剂。 相似文献
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红景天苷及其衍生物体外清除自由基作用的研究 总被引:14,自引:1,他引:14
目的 研究红景天苷及其衍生物体外清除羟自由基(OH·)和超氧阴离子自由基(O-·2 )的能力。方法 用电子顺磁共振(EPR)波谱仪,检测①由二甲基亚砜(DMPO)自旋捕获Fenton反应产生的OH·的加合物的信号强度。②DMSO在碱性有氧条件下产生的O-·2 ;根据加入受试化合物前后EPR谱线强度的变化,计算受试化合物清除自由基的效率。结果 1 ( 3 羟基)苯乙基βD 吡喃半乳糖苷清除OH·和O-·2 的作用最强,优于红景天苷。结论 苯环上基团及其位置的改变、糖的类型,可以影响红景天苷清除自由基的能力,其中糖基对化合物清除作用的影响最大。 相似文献
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白花前胡香豆素组分体外抗氧化活性研究 总被引:1,自引:0,他引:1
目的 观察白花前胡香豆素组分(TCP)对氧自由基的清除作用及其对脂质过氧化反应的抑制作用。方法羟自由基由Fenton反应体系产生,超氧阴离子自由基由邻苯三酚自氧化法产生,采用硫代巴比妥酸法测定肝匀浆丙二醛(MDA)相对含量来反映TCP对脂质过氧化的影响。结果TCP对羟自由基和超氧阴离子自由基有较强的清除作用,达到50%清除率所需药物浓度(EC50)分别为287.1和124.8 μg8226;mL 1,并抑制小鼠肝匀浆脂质过氧化反应,EC50为409.5 μg8226;mL 1。结论TCP对氧自由基有清除作用,并抑制脂质过氧化反应,其活性与剂量呈正相关。 相似文献
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异莲心碱的体外抗氧化活性 总被引:10,自引:1,他引:10
目的研究异莲心碱对氧自由基的清除作用及其对脂质过氧化反应(LPO)的抑制作用。方法羟自由基由Fenton体系产生,超氧阴离子自由基由邻苯三酚自氧化法产生,通过比色法测定LPO的终产物 丙二醛(MDA)的相对含量来反映异莲心碱对LPO的影响。结果异莲心碱对羟自由基和超氧阴离子自由基有较强的清除作用,达到5 0 %清除率所需药物浓度(EC50 )分别为0 .90 ,1.82mg/ml,可抑制小鼠肝匀浆脂质过氧化反应,EC50 为0 .6 7mg/ml。结论异莲心碱对氧自由基有清除作用,对脂质过氧化有抑制作用,其活性与剂量呈正相关 相似文献
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2—羟甲基—3,5,6—三甲基吡嗪的合成及其对血液流变性的影响 总被引:7,自引:0,他引:7
合成了川芎嗪体内主要代谢产物8-羟甲基-3,5,6-三甲基吡嗪,以川芎嗪为阳性对照观察了它的血液流变的影响,发现两者无显著差别。 相似文献
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Elaine S. Coimbra Rafael Carvalhaes Richard M. Grazul Patricia A. Machado Marcos V. N. De Souza Adilson D. Da Silva 《Chemical biology & drug design》2010,75(6):628-631
We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells. 相似文献
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Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.
Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.相似文献
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Petrikovics I McGuinn WD Sylvester D Yuzapavik P Jiang J Way JL Papahadjopoulos D Hong K Yin R Cheng TC DeFrank JJ 《Drug delivery》2000,7(2):83-89
This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine. 相似文献
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Lung disease and PKCs 总被引:1,自引:0,他引:1
The lung offers a rich opportunity for development of therapeutic strategies focused on isozymes of protein kinase C (PKCs). PKCs are important in many cellular responses in the lung, and existing therapies for pulmonary disorders are inadequate. The lung poses unique challenges as it interfaces with air and blood, contains a pulmonary and systemic circulation, and consists of many cell types. Key structures are bronchial and pulmonary vessels, branching airways, and distal air sacs defined by alveolar walls containing capillaries and interstitial space. The cellular composition of each vessel, airway, and alveolar wall is heterogeneous. Injurious environmental stimuli signal through PKCs and cause a variety of disorders. Edema formation and pulmonary hypertension (PHTN) result from derangements in endothelial, smooth muscle (SM), and/or adventitial fibroblast cell phenotype. Asthma, chronic obstructive pulmonary disease (COPD), and lung cancer are characterized by distinctive pathological changes in airway epithelial, SM, and mucous-generating cells. Acute and chronic pneumonitis and fibrosis occur in the alveolar space and interstitium with type 2 pneumocytes and interstitial fibroblasts/myofibroblasts playing a prominent role. At each site, inflammatory, immune, and vascular progenitor cells contribute to the injury and repair process. Many strategies have been used to investigate PKCs in lung injury. Isolated organ preparations and whole animal studies are powerful approaches especially when genetically engineered mice are used. More analysis of PKC isozymes in normal and diseased human lung tissue and cells is needed to complement this work. Since opposing or counter-regulatory effects of selected PKCs in the same cell or tissue have been found, it may be desirable to target more than one PKC isozyme and potentially in different directions. Because multiple signaling pathways contribute to the key cellular responses important in lung biology, therapeutic strategies targeting PKCs may be more effective if combined with inhibitors of other pathways for additive or synergistic effect. Mechanisms that regulate PKC activity, including phosphorylation and interaction with isozyme-specific binding proteins, are also potential therapeutic targets. Key isotypes of PKC involved in lung pathophysiology are summarized and current and evolving therapeutic approaches to target them are identified. 相似文献
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Chang Min Kim Kun Ho Son Sung Hwan Kim Hyun Pyo Kim 《Archives of pharmacal research》1991,14(4):305-310
In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins
from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins. 相似文献