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1.
目的 探讨天麻素(Gastrodine,Gas)对大鼠局灶性脑缺血损伤的保护作用及机制.方法 线栓法制备大鼠大脑中动脉栓塞模型,缺血2h后再灌注.天麻素(5,10,20 mg/kg)再灌注同时腹腔给药,再灌注后24 h,测定大鼠神经功能缺失评分和脑梗死体积,伊文思蓝法观察血脑屏障破坏程度,Western blot检测梗死半暗带皮层组织炎症因子TNF-α、IL-1β和IL-6的蛋白表达.结果 天麻素(10,20 mg/kg)能改善大鼠脑缺血后神经功能缺失,减小脑梗死体积,降低血脑屏障的通透性.天麻素(20 mg/kg)对梗死半暗带皮层组织TNF-α表达的抑制率为24%,对IL-1β表达的抑制率为34%,对IL-6表达水平的抑制率为38%.结论 天麻素可降低血脑屏障的通透性,其通过减低炎症反应而对局灶性脑缺血损伤发挥保护作用.  相似文献   

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目的:观察葡萄籽原花青素(GSP)对大鼠脑缺血再灌注损伤中羟自由基含量和肿瘤坏死因子-α(TNF-α)表达的影响。方法 Wistar大鼠48只随机分为四组:假手术组、缺血再灌注模型组、GSP大剂量(40 mg/kg)组、GSP小剂量(10 mg/kg)组,每组12只,应用线栓法制作大鼠大脑中动脉栓塞模型(MCAO),缺血2 h再灌注24 h。假手术组手术过程相同但不栓塞大脑中动脉。其中GSP大剂量组、小剂量组术前7 d分别腹腔注射2 ml/kg葡萄籽原花青素,模型组大鼠术前7 d腹腔注射2 ml/kg生理盐水,1次/d,再灌注前15 min加注1次。MCAO模型制作完成后首先进行神经功能评分,然后利用生物化学技术检测大鼠血清羟自由基含量和一氧化氮合酶活性,免疫组织化学染色检测半暗带区颞顶部脑皮质神经细胞TNF-α的表达。结果 GSP对大鼠脑缺血再灌注损伤有保护作用。其机制可能与降低NOS活性、脑组织羟自由基含量,降低脑组织TNF-α的表达,抑制神经细胞凋亡等有关。结论 GSP对脑缺血再灌注损伤具有一定的保护作用,具有临床研究价值。  相似文献   

3.
刘和兰  李健哲  梁荣寿 《现代医药卫生》2014,(10):1446-1448,1451
目的探讨川芎嗪对大鼠局灶性脑缺血再灌注损伤的保护作用及机制。方法将64只健康雄性SD大鼠随机分为四组:(1)假手术组;(2)缺血再灌注组;(3)川芎嗪20 mg/kg处理组;(4)川芎嗪40 mg/kg处理组。每组各16只,8只用于脑梗死体积测定,8只用于mRNA和蛋白的测定。采用线栓法制备大鼠局灶性大脑中动脉栓塞模型,缺血2 h再灌注24 h。术后对大鼠神经功能进行评分;2,3,5-氯化三苯四氮唑染色观察脑梗死体积;酶联免疫吸附法测定脑组织中肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)和核因子-κBp65(NF-κBp65)水平;实时定量聚合酶链反应和蛋白质印迹法分别检测Toll样受体4(TLR4)mRNA和蛋白的表达。结果与假手术组比较,缺血再灌注组大鼠的神经功能缺陷评分和脑梗死体积明显增加;脑组织中TNF-α、IL-1β和NF-κBp65水平以及TLR4的表达也显著升高,差异均有统计学意义(P〈0.05)。川芎嗪处理组上述指标,与缺血再灌注组比较,差异有统计学意义(P〈0.05);不同剂量川芎嗪处理组间比较,差异无统计学意义(P〉0.05)。结论川芎嗪可抑制脑缺血再灌注诱导的损伤,其机制与抑制TLR4/NF-κB信号通路,进而减少炎症因子的产生有关。  相似文献   

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目的研究脑脉泰对大鼠局灶性脑缺血再灌注损伤NOS和氧自由基的影响。方法大脑中动脉线拴法(MCAO)制作大鼠局灶性脑缺血再灌注模型:60只雄性SD大鼠随机分为假手术组(sham)、脑缺血再灌注模型组(MCAO)、脑脉泰大、中、小(2.24、1.12、0.56g/kg)剂量组和尼莫地平组(10mg‘kg),每组10只大鼠。术后取梗死侧脑组织做成匀浆,检测脑组织中丙二醛(MDA)、乳酸(LA)、超氧化物歧化酶(SOD)和谷胱甘肽(GSH)含量。免疫组化染色检测缺血半暗带iNOS和eNOS蛋白表达。结果脑组织匀浆生化指标检测发现缺血脑脉泰能显著降低脑组织中MDA和IA含量;升高SOD和GSH含量,脑缺血半暗带的eNOS蛋白表达明显增加,iNOS表达显著减少,与MCAO模型组比较,有显著性差异(P〈0.05)。结论脑脉泰能减少脑缺血/再灌注损伤,其保护作用与增加脑组织的抗氧化能力和eNOS/iNOS有关。  相似文献   

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目的 探究黄芪甲苷调节白介素-10(IL-10)/β-内啡肽(β-EP)信号通路对腰椎间盘突出症(LDH)大鼠神经根损伤的影响。方法 随机选择10只大鼠记为假手术组(Sham组),其余大鼠通过移植髓核构建LDH大鼠模型,将造模成功大鼠随机分为LDH组、黄芪甲苷组(20 mg/kg黄芪甲苷)、 AS10组(0.5 mg/kg IL-10/β-EP信号通路抑制剂AS10)、黄芪甲苷+AS10组(20 mg/kg黄芪甲苷+0.5 mg/kg AS10),每组10只,Sham组和LDH组给予等量0.9%氯化钠溶液。机械刺激敏感性实验以及热刺激敏感性实验检测大鼠机械缩足阈值(PWT)以及热痛阈(TWL);ELISA法检测血清白介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)水平;免疫荧光染色测定小胶质细胞和星形胶质细胞活性;TUNEL染色检测细胞凋亡;Western blot检测IL-10、β-EP蛋白表达。结果 与Sham组比较,LDH组PWT值、TWL值、IL-10、β-EP蛋白水平显著减小(P<0.05),细胞凋亡率、TNF-α、IL-1β水平、离子钙接头蛋白分子1(Iba1...  相似文献   

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目的 考察灵仙新苷对大鼠心肌缺血再灌注损伤(MIRI)的保护作用,并阐述可能的作用机制。方法 SD大鼠随机分为6组:假手术组、模型组、丹参酮ⅡA(阳性药,16 mg/kg)组和灵仙新苷低、中、高(8、16、32 mg/kg)组,连续ig给药7 d;采用结扎冠状动脉左前降支法制备大鼠MIRI模型,缺血40 min再灌120 min;试剂盒法检测MIRI大鼠血清肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白介素-6(IL-6)水平;TTC染色法检测心肌梗死率,流式细胞术检测心肌细胞凋亡率;Western blotting法检测心肌组织中Bcl-2、Bax、TNF-α及Caspase-3的蛋白表达水平。结果 与模型组比较,灵仙新苷(8、16、32 mg/kg)显著降低MIRI模型大鼠血清中TNF-α、IL-1β、IL-6水平,心肌梗死率和心肌细胞凋亡率;明显上调Bcl-2蛋白表达水平,下调Bax、TNF-α、Caspase-3蛋白表达水平,且均具有显著性差异(P<0.05、0.01)。结论 灵仙新苷对MIRI大鼠心肌具有保护作用,其机制可能与抑制TNF-α,调节Bcl-2/Bax蛋白平衡,减少MIRI诱导的心肌细胞凋亡有关。  相似文献   

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目的 探讨芦丁对脑缺血再灌注损伤的作用及机制.方法 30只SD大鼠随机分为3组.模型组和芦丁组采用线栓法构建大脑中动脉局灶缺血(1.5 h)再灌注损伤模型,芦丁组在缺血前15 min腹腔注射芦丁(10 mg/kg),模型组腹腔注射等量生理盐水.术后24 h处死大鼠,收集脑组织和血清,HE染色观察脑组织病理形态学变化,ELISA检测和RT-PCR检测脑组织促炎症细胞因子TNF-α,IL-1β和IL-8的表达变化,Western Blot检测脑组织中Wnt,β-catenin,cyclin D 1和survivin的表达变化.结果 芦丁可减轻脑缺血再灌注损伤大鼠的脑组织病理形态学变化,Wnt和β-catenin的表达和促炎症细胞因子TNF-α,IL1β和IL-8表达(P<0.05).结论 芦丁可通过抑制Wnt/β-catenin信号途径介导的炎性反应而减轻脑缺血再灌注损伤.  相似文献   

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目的 观察木犀草素减轻大鼠脑缺血再灌注损伤的作用并探讨其潜在机制。方法 SD大鼠按随机数字 表法分为假手术组、大脑中动脉栓塞(MCAO)组、木犀草素低剂量组(50 mg/kg)、木犀草素高剂量组(100 mg/kg)及尼 莫地平组(15 mg/kg),灌胃给药,共7 d。采用线栓法建立MCAO大鼠模型,比较神经功能损伤评分、脑组织含水量、 脑梗死体积,测定各组肿瘤坏死因子α(TNF-α)、白细胞介素(IL)-6、IL-1β、B细胞淋巴瘤因子2(Bcl-2)、Bcl-2相关 X蛋白(Bax)、半胱氨酸蛋白酶3(Caspase-3)含量及磷酸化Janus蛋白酪氨酸激酶2(p-JAK2)、磷酸化信号转导及转 录激活蛋白3(p-STAT3)蛋白表达等变化情况。结果 与假手术组比较,MCAO组大鼠神经功能损伤评分、脑组织含 水量、脑梗死体积、脑组织TNF-α、IL-6、IL-1β、Bax、Caspase-3含量及JAK2、STAT3蛋白磷酸化水平均明显增加(P< 0.05),而脑组织Bcl-2含量明显降低(P<0.05);与MCAO组比较,木犀草素低、高剂量组及尼莫地平组大鼠神经功能 损伤评分、脑组织含水量、脑梗死体积、脑组织TNF-α、IL-6、IL-1β、Bax、Caspase-3含量及JAK2、STAT3蛋白磷酸化 水平均明显降低(P<0.05),而脑组织Bcl-2含量明显增加(P<0.05)。结论 木犀草素具有减轻大鼠脑缺血再灌注 损伤的作用,该作用与抑制JAK2/STAT3信号通路活化,进而减弱炎症反应及减少细胞凋亡有关。  相似文献   

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目的观察依达拉奉对脑缺血再灌注损伤大鼠脑组织Fas及细胞凋亡的影响。方法24只雄性SD大鼠随机分为三组:假手术组(SH组)、缺血再灌注组(IR组)、依达拉奉治疗组(EDA组),每组8只。IR组和EDA组线栓法制备脑缺血再灌注模型;SH组栓线只进入颈外动脉。EDA组于再灌注前30min和再灌注12h经腹腔注射依达拉奉3mg/kg,SH组和IR组在相同时间点注射等容量生理盐水。再灌注24h取血清测超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量;取脑组织检测缺血半暗带Fas的表达及细胞凋亡情况;于再灌注3h和24h,参照Zealonga五级神经功能缺损评分标准评价神经功能损伤情况。结果与SH组比较,IR组和EDA组再灌注24h血清SOD活力降低(P〈0.01),IR组SOD活力低于EDA组(P〈0.01)。与SH组比较,IR组和EDA组再灌注24h时血清MDA含量升高(P〈0.01);IR组MDA含量高于EDA组(P〈0.05)。SH组脑组织无或仅有少量细胞Fas表达呈阳性,IR组与EDA组缺血半暗带均有大量Fas表达;EDA组平均灰度值较IR组大(P〈0.01)。SH组脑组织仅有少量凋亡细胞,IR组与EDA组缺血半暗带可见大量凋亡神经细胞;EDA组凋亡细胞数较IR组少(P〈0.01)。SH组各时点无神经损伤症状,再灌注3h,IR组与EDA组大鼠神经功能损伤差异无显著性(P〉0.05);再灌注24h,与IR组比较EDA组大鼠神经功能损伤减轻(P〈0.05)。结论脑缺血再灌注后,大鼠血清SOD活力降低、MDA含量升高、大脑皮层半暗带Fas表达及凋亡细胞数明显增多。依达拉奉可保护SOD活力,降低MDA含量,减少缺血再灌注大脑皮层半暗带Fas的表达及细胞凋亡,从而减轻神经功能损伤,对脑缺血再灌注损伤具有一定的保护作用。  相似文献   

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目的观察康脑液1号对SD大鼠脑缺血再灌注细胞凋亡及胶质纤维酸性蛋白(GFAP)表达的影响,探讨其对脑缺血再灌注保护作用的可能机制。方法采用栓线法复制SD大鼠大脑中动脉梗死模型(MCAO),分别于缺血2h后再灌注1d、3d、7d。将180只大鼠随机分为5组(每组36只):假手术组,模型(缺血再灌注)组,盐酸法舒地尔注射液组,康脑液1号A组,康脑液1号B组。观察康脑液1号对大鼠脑缺血再灌注神经功能、脑梗死面积和病理形态学的影响。采用TUNEL法检测缺血半暗带和灶中心区凋亡细胞,采用免疫组化法检测缺血半暗带和灶中心区GFAP表达的变化。结果模型组与假手术组相比,缺血半暗带凋亡细胞及GFAP阳性细胞数目增多(P〈0.05)。康脑液1号可不同程度地降低实验性脑缺血大鼠的神经功能评分、减小梗死灶面积并减轻脑组织病理形态改变(P〈0.05);康脑液1号2组大鼠脑组织缺血半暗带凋亡细胞和GFAP表达减少,而梗死灶中心凋亡细胞和GFAP表达却增多。结论康脑液1号可能通过调节脑缺血再灌注细胞凋亡和GFAP表达而促进脑损伤修复及重塑,从而发挥脑保护作用。  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.
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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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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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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   

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Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.  相似文献   

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