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81.
蕲蛇酶对大鼠脑缺血再灌注损伤的保护作用   总被引:5,自引:0,他引:5  
目的进一步探讨蕲蛇酶对大鼠脑缺血再灌注损伤的保护作用及其机制。方法采用线栓法制备大鼠大脑中动脉闭塞后再灌注(MCAOR)模型,观察大鼠MCAOR时神经功能状态,同时,TTC染色测脑梗死面积,电镜观察脑血管超微结构,放免法测定血浆血栓素B2及6-酮前列腺素F1α含量。用药组分别在缺血即刻或再灌注即刻静脉给药,观察比较模型组和蕲蛇酶所有给药组之间上述指标的变化。结果蕲蛇酶所有给药组都能有效改善MCAOR大鼠神经功能缺失症状,明显减小梗死灶,调节血栓素B2/6-酮前列腺素F1α,保护血管内皮细胞,维持微血管正常结构。结论蕲蛇酶对脑缺血再灌注损伤保护作用可能与维持血栓素B2/6-酮前列腺素F1α平衡、改善脑微循环有关。  相似文献   
82.
银杏内酯B对慢性炎症血管生成的抑制作用   总被引:1,自引:0,他引:1  
目的研究银杏内酯B对慢性炎症血管生成的作用及部分作用机制。方法比色法测定小鼠慢性肉芽肿气囊模型血管生成指数,组织形态学方法检测气囊病理变化;放射免疫方法测定白介素-1β(IL-1β)含量;L929生物测定法测定肿瘤坏死因子(TNF-α)含量;RT-PCR法检测IL-1β和TNF-α mRNA的表达。结果银杏内酯B可显著抑制模型小鼠的血管指数,与病理观察结果相符;银杏内酯B可显著抑制模型小鼠血清中IL-1和TNF-α的分泌;能显著抑制PMA诱导的U937细胞IL-1β和TNF-α的分泌及其mRNA的表达。结论银杏内酯B能抑制小鼠慢性炎症性血管生成模型的血管生成,能抑制促血管生成细胞因子IL-1β和TNF-α的转录及表达,这可能是其抑制慢性炎症血管生成的机制之一。  相似文献   
83.
目 的 探 讨 1α,25-二羟 维生 素 D_3(1α,25-(OH )2D )对 系 统性 红斑 狼 疮(SLE)患 者 外周 血 单个 核 3细 胞(PBM C)分 泌的 白细 胞 介素 (IL)-10 和 干扰 素 (IFN )-α水平 的 影响 。方法 20 例 SLE 患 者和 10 名健 康 志愿者 PBM C 的提 取 采 用 Ficol密 度 梯 度 离 心 法 ,SLE 组 和 对 照 组 在 不 加 或 加 入 1α,25-(O H )2D3 的 情 况 下 孵 育 72 h收 集培 养 上清 ,上 清液 IL-10 和 IFN-α水平 检 测采 用酶 联 免疫 吸附 试 验(ELISA )。结 果 与 正常 对 照组 相比 ,SLE组 PBM C 中 IL-10 和 IFN-α水 平 明 显 增高 (P<0.01)。0.01 m ol/L 1α,25-(O H )2D3 的 加 入 明 显 抑 制 了 SLE 组PBM C 中 IFN -α的 产 生 (P<0.01),增 加 了 SLE 组 PBM C 中 IL-10 的 产 生 (P<0.01),但 对 正 常 对 照 组 IFN -α和IL-10 水平 无明 显 影响 。结 论 1α,25-(OH )2D 可 能 抑制 体外 培 养的 SLE 患 者 PBM C IFN -α的产 生  相似文献   
84.
Infiltration of circulatory inflammatory cells is a common histopathological finding in target organs following cadmium administration, but there is paucity of data concerning their activity. In this study, the effects of sublethal (1 mg/kg) cadmium on peripheral blood polymorphonuclear (PMN) cells were examined 48 h following administration in rats, when tissue (liver and lung) infiltration of these cells was observed. Cadmium administration resulted in systemic inflammatory cytokine and acute phase response with an increase in circulatory neutrophil numbers and cells that express CD11b molecules. Rise in basic aspects of oxidative activity including intracellular myeloperoxidase (MPO), reactive oxygen (nitroblue tetrazolium/NBT cytochemical assay) and nitrogen (Griess assay) species production was observed in PMNs from cadmium-administered rats. A decrease in levels of mRNA for IL-1β, TNF-α and IL-6 was noted, but production of these cytokines was affected differentially. Described effects of cadmium on PMNs add further to the understanding of inflammatory potential of this environmental contaminant.  相似文献   
85.
86.
《Drug metabolism reviews》2012,44(1-2):89-116
Dehydroepiandrosterone has been thought to have physiological functions other than as an androgen precursor. The previous studies performed have demonstrated a number of biological effects in rodents, such as amelioration of disease in diabetic, chemical carcinogenesis, and obesity models. To date, activation of the peroxisome proliferators activated receptor alpha, pregnane X receptor, and estrogen receptor by DHEA and its metabolites have been demonstrated. Several membrane-associated receptors have also been elucidated leading to additional mechanisms by which DHEA may exert its biological effects. This review will provide an overview of the receptor multiplicity involved in the biological activity of this sterol.  相似文献   
87.
Abstract

Pancreatic cancer is one of the deadliest cancers across the world with an average 5-year survival rate of less than <6%. In this study, gemcitabine (GEM) and HIF1α-siRNA loaded GE-11 peptide conjugated liposome was successfully prepared and evaluated for its antitumor efficacy in pancreatic cancer cells. The GE11 increased the targeting specificity of liposome carrier and increased the intracellular concentrations in the cancer cells. Furthermore, synergistic combination of GEM and HIF1a-siRNA exhibited remarkable improvement in the declining of cancer cell proliferations. siRNA could effectively decrease the expression of HIF1a gene in the cancer cells. Importantly, GE-11 peptide-conjugated GEM/siRNA-loaded liposomes (GE-GML/siRNA) increased the total amount of apoptosis cells with higher proportion of cells in late apoptosis phase. GE-GML induced remarkable apoptosis of cancer cells and induced chromatin condensation and nuclear fragmentation which are considered to be typical features of apoptosis and cell death. GE-GML/siRNA showed a significant reduction in the tumour burden suggesting the superior anticancer efficacy of this formulation. GE-GML/siRNA showed four-fold reduction in tumour compared to control and two-fold reduction compared to GE-GML, respectively. Overall, present work lays foundation for the combination of GEM and HIF1a-siRNA loaded in a targeted nanocarrier system as a unique therapeutic option in pancreatic cancer treatment.  相似文献   
88.
The editor welcomes for publication short news items of interest to readers of this journal, and especially details of forthcoming symposia and conferences concerned with subjects pertinent to the field.  相似文献   
89.
《Drug metabolism reviews》2012,44(4):553-624
The aldo-keto reductase (AKR) superfamily comprises enzymes that catalyze redox transformations involved in biosynthesis, intermediary metabolism, and detoxification. Substrates of AKRs include glucose, steroids, glycosylation end-products, lipid peroxidation products, and environmental pollutants. These proteins adopt a (β /α )8 barrel structural motif interrupted by a number of extraneous loops and helixes that vary between proteins and bring structural identity to individual families. The human AKR family differs from the rodent families. Due to their broad substrate specificity, AKRs play an important role in the phase II detoxification of a large number of pharmaceuticals, drugs, and xenobiotics.  相似文献   
90.
《Drug delivery》2013,20(1):84-89
A transdermal drug delivery system has been reported that can increase the bioavailability, reduce the administration duration, and maintain the concentration of drug in blood. In the present study, drug-in-adhesive transdermal patches of α-asarone using Eudragit E100 as pressure-sensitive adhesives and oleic acid plus isopropyl myristate as penetration co-enhancers were developed. In vitro permeation, in vivo pharmacokinetics in rabbits, and efficacy in asthmatic rats were evaluated. The results showed that co-enhancers could induce a synergistic effect on α-asarone permeability. In vivo study suggested that the patch can keep a relatively certain blood level of drug within 10–30?h in rabbits. Furthermore, the patch with the size of 4?cm2 containing drug 3?mg/cm2 showed a noticeable treating effect on asthmatic rats which is equivalent to the effect of dexamethasone, while avoiding the side-effect induced by the corticorsteroid. This suggests that the drug-in-adhesive transdermal patch is a promising delivery system containing α-asarone to be used for asthma treatment.  相似文献   
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