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1.
目的 通过生物传感器技术,应用常规分离技术寻找赤芍中的非鞣质类的抗LPS活性成分。方法 以生物传感器技术和薄层色谱技术为指导,建立赤芍抗LPS成分的有效提取方法。再利用高效液相色谱技术(HPLC)从赤芍中定向分离出具有拮抗LPS作用的活性组分。最后对其进行拮抗LPS活性的药理学评价。结果 利用生物传感器技术完成了对不同产地和不同煎煮方法的赤芍拮抗LPS活性的筛选,确定出醇提法的四川的赤芍中拈抗LPS活性成分的含量最高。并从中定向分离出6个具有与Lipid A结合活性的组分。  相似文献   

2.
目的:脓毒症是感染因素介导的全身炎症反应综合征,至今无有效的治疗手段。细菌Cp6DNA是引起脓毒症的主要病原分子。CpGDNA通过与TLR9结合,介导单核/巨噬细胞的活化,是介导脓毒症发生的重要途径。本研究以CpGDNA为靶点,从中药中定向分离具有拮抗CpGDNA和治疗脓毒症作用的活性物质。方法:(1)应用生物传感器技术、建立以CpGDNA为靶点的筛选抗炎中药的技术平台并对78种中药进行筛选;(2)利用生物传感器技术、硅胶柱层析、离子交换柱层析技术,从大黄中定向分离与CDGDNA具有较高结合活性的组分,并对得到的组分进行初步的活性评价,确定活性组分;(3)在体外实验中,测定活性组分与CpGDNA、lipidA的结合能力,观察活性组分对LPS、CpGDNA刺激小鼠RAW264.7细胞分泌炎症介质的抑制作用,在体内实验中,观察活性组分对致死剂量热灭活大肠杆菌攻击小鼠的保护作用。(4)利用反相HPLC技术对活性组分进行制备分离,获得活性单体化合物;(5)在体外实验中,检测单体化合物与CpGDNA和lipidA的结合能力.观察化合物对LPS、CpGDNA刺激小鼠RAW264.7细胞分泌炎症介质的抑制作用。结果:(1)建立了以CpGDNA为靶点应用生物传感器筛选抗炎中药的技术平台;从78种中药中筛选出大黄等14种中药与CpGDNA具有较高结合能力;(2)利用生物传感器技术、硅胶柱层析、离子交换柱层析等技术从大黄水提物中定向分离得到与CpGDNA有较高结合活性大黄D组分;(3)在体外,大黄D组分与CpGDNA、LipidA均具有较高的结合活性,对CpGDNA及LPS刺激小鼠RAW264.7细胞分泌TNF-α有显著的抑制活性,并呈现良好的量一效关系。在体内,大黄D组分对致死剂量的热灭活大肠杆菌攻击小鼠有显著的保护作用,并呈现良好的量-效关系;(4)通过反相HPLC从D组分中分离得到单体化合物大黄酸和大黄素;(5)在体外,大黄酸和大黄素与CpGDNA均具有较高结合能力,均能单独或协同对CpGDNA及LPS刺激RAW264.7细胞分泌TNF—Q产生显著抑制作用。结论:(1)应用生物传感器、以病原分子CpG DNA为靶点,成功地建立了筛选抗炎中药的技术平台;(2)从大黄中分离得到与CpGDNA有较高结合活性的大黄D组分,体内、外生物学活性评价结果显示:大黄D组分对CpGDNA及LPS刺激小鼠RAW264.7细胞分泌TNF—α具有显著的抑制活性,并对致死剂量的热灭活大肠杆菌攻击小鼠有显著的保护作用;(3)从大黄D组分中分离得到单体化合物大黄酸和大黄素,生物学活性评价结果显示,大黄酸和大黄素对CpGDNA及LPS刺激小鼠RAW264.7细胞分泌TNF—α具有显著的抑制活性,提示大黄酸和大黄素可能是D组分以及大黄提取物拮抗cpGDNA和脓毒症的主要物质基础。  相似文献   

3.
赤芍拮抗内毒素活性的实验研究   总被引:11,自引:0,他引:11  
目的:提取分离中药赤芍中拮抗内毒素(LPS)的有效成分并进行药理学活性检测。方法:通过生物传感器,结合常规的中药分离技术,分离提取出赤芍拮抗LPS的有效成分,应用鲎实验和ELISA法检测该有效成分对LPS的中和作用。结果:赤芍中的有效成分与LPS具有较高的结合作用,该结合作用具有较强的中和LPS活性,在体外能够显著抑制由LPS介导小鼠RAW 2 6 4.7细胞释放TNF α。结论:以LPS为靶点,应用生物传感器技术,可快速、有效地提取分离赤芍中具有较强的中和LPS活性的有效成分。  相似文献   

4.
栀子苷拮抗内毒素的实验研究   总被引:2,自引:1,他引:1  
目的 研究栀子苷的抗内毒素/脂多糖生物学活性。方法 应用生物传感器技术检测栀子苷与LPS活性中心Lipid A的结合活性、动态比浊法鲎试验检测栀子苷(0、2.5、5.0、10.0 mg/L)对LPS(0.1 μg/L)的中和活性、ELISA法检测栀子苷(0、25、50、100 mg/L)对LPS(100 μg/L)刺激RAW264.7细胞释放细胞因子的影响,进而观察栀子苷(0、10、20、40 mg/kg)对致死剂量LPS攻击模型小鼠的保护作用。结果 栀子苷与Lipid A具有结合活性,量效关系明显;栀子苷(2.5、5.0、10.0 mg/L)在体外对LPS(0.1 μg/L)具有显著的直接中和作用(P<0.01);栀子苷在50-100 mg/L浓度水平能够显著抑制LPS(100 μg/L)刺激RAW264.7细胞释放TNF-α(P<0.01);40 mg/kg的栀子苷对脓毒症模型小鼠具有显著的保护作用(P<0.01)。结论 栀子苷可能通过与Lipid A结合中和LPS的活性,抑制LPS介导的细胞活化,减少细胞因子释放,进而保护脓毒症模型小鼠。  相似文献   

5.
以Lipid A为靶点拮抗内毒素中药的筛选   总被引:1,自引:0,他引:1  
目的利用生物传感器跟踪技术从抗炎中药中筛选出具有拮抗内毒素的中药,为进一步对中药拮抗内毒素活性成分的分离纯化提供实验依据。方法将革兰阴性细菌的脂质A(Lipid A)包被于生物传感器的非衍生板建立靶点,跟踪测定赤芍、大黄、黄芩等78种中药的水提物和醇提物与Lipid A的结合活性,再将筛选出的中药去鞣质后与定量的内毒素(LPS,20、50ng·ml-1)37℃孵育30min后,测定孵育后的样品与Lipid A的结合情况,以评价样品内的活性物质含量。结果在所筛选的78种中药中有12种中药的水提物与Lipid A具有较高的亲和活性,在这12种中药中有6种中药的醇提物与Lipid A也具有较高的亲和活性;通过对所筛选出的12种中药的水提物去除鞣质后与LPS的消耗实验,发现所筛选出的12种中药均含有除鞣质以外的与lipid A具有特异性结合的物质,并且12种中药中能与Lipid A发生特异性结合作用的活性物质含量存在较大的差异。结论生物传感器跟踪技术是一种快速、准确、有效的筛选平台,筛选出的12种中药均含有非鞣质类能与lipid A发生特异性结合作用的物质,为进一步对12种中药抗内毒素有效部位或单体的分离提供了重要的实验依据。  相似文献   

6.
目的:通过对高密度脂蛋白(HDL)体内外生物学活性实验研究,探讨HDL对内毒素的中和作用。方法:应用勤和生物传感器技术检测HDL与LPS的结合活性,采用ELISA方法检测HDL对LPS攻击小鼠的保护作用等试验来阐明HDL对LPS的中和效果。结果:应用亲和生物传感器亲和力检测,结果发现HDL与lipidA之间具有很高的.木和能力;HDL可以显抑制LPS刺激小鼠RAW264.7细胞释放TNF—α,并成量效关系;在小鼠体内使用剂量为120mg/kg的HDL可以明显保护致死剂量LPS攻击小鼠,保护率达到70%。结论:HDL在体内外与LPS结合,从而抑制了LPS的生物学活性,被认为是一种内毒素清除剂,对防治脓毒症具有临床指导意义,  相似文献   

7.
目的:从金黄色葡萄球菌中提取纯化可溶性肽聚糖并鉴定其活性。方法:采用小剂量青霉素作用金黄色葡萄球菌(ATCC25923),诱导合成可溶性肽聚糖(PGN)粗品,经Sephadex G-100凝胶层析进一步分离纯化;采用SLP试剂盒对纯化的可溶性PGN定性,ELISA法检测纯化的可溶性PGN对小鼠RAW264.7细胞的活化作用。结果:分离纯化的可溶性PGN经SLP试剂检测阳性,该可溶性PGN可刺激RAW264.7细胞释放TNF-α,并具有明显的量效关系。结论:采用青霉素诱导结合凝胶层析技术可从金黄色葡萄球菌获取纯度及生物学活性较高的可溶性PGN。  相似文献   

8.
目的:脓毒症是感染因素介导的全身炎症反应综合征,是烧伤、创伤和感染性疾病患者的常见并发症,其中内毒素(LPS)是介导细菌脓毒症的重要病原体相关分子模式。重组人活化蛋白C作为FDA批准的第一个用于治疗重度脓毒症的药物,经过6年的应用评估,其疗效已被否定,迄今脓毒症治疗仍缺乏有效药物。本文通过从中药栀子中提取分离具有中和LPS作用的有效成分京尼平苷,研究其拮抗细菌脓毒症的活性。方法:以LPS活性中心LipidA为靶点,采用生物传感器技术,从传统清热中药中筛选出具有LipidA结合活性的栀子,进而利用现代色谱技术分离出具有拮抗LPS活性的单体京尼平苷,通过鲎试剂法检测京尼平苷对LPS的体内外中和作用;RT-PCR法检测京尼平苷对LPS诱导巨噬细胞TLR4和TNF—αmRNA表达的影响;ELISA法检测京尼平苷对LPS刺激RAW264.7细胞产生细胞因子(TNF—α)的抑制作用;观察京尼平苷对脓毒症模型小鼠的保护作用。结果:京尼平苷在体外对LPS具有直接的中和作用,并呈现出较好的剂量效应关系:同时可剂量依赖的抑制LPS刺激引起的RAW264.7细胞的活化(TLR4和TNF-αmRNA的表达下调,细胞因子TNF-α的产生减少);在体内可降低LPS血症模型动物血中的LPS水平;对致死剂量热灭活大肠埃希氏菌攻击的小鼠具有显著的保护作用。  相似文献   

9.
目的:寻找有效的抑制性CpG ODN,并研究其对刺激CpG ODN(CpG-S ODN)1826诱导细胞分泌TNF-α的影响及其作用机制和对脓毒症小鼠的影响。方法:选用本室前期采用生物信息学技术合成的21种CpG ODN,筛选出对CpG-S ODN诱导hPBMC释放TNF-α具有抑制作用的CpG-N ODN;采用亲和传感技术观察该CpG-NODN与CpG-S ODN间的相互结合;采用流式细胞技术观察CpG-NODN对的影响;并采用RT-PCR技术和EMSA技术观察CpG-N ODN对CpG-S ODN诱导的hPBMC TLR9表达的影响以及NF-xB活化的影响。同时观察了CpG-N 0DN对脓毒症小鼠的保护作用,并检测小鼠血清TNF-α水平。结果:从前期合成的CpG ODN中成功的筛选出了能有效抑制CpG-S ODN诱导hPBMC释放TNF-α的CpG-N ODN,并发现当浓度比为3:5,4:5,和1:1时均能有效抑制CpG-S ODN对hPBMC的刺激活性,其中浓度比为1:1的CpG-N ODN对刺激性CpG-S ODN诱导hPBMC分泌TNF-α抑制作用最强,并呈一定时效关系;应用亲和传感技术可以看出CpG-SODN与CpG-NODN没有直接结合作用;同时CpG-NODN还可以明显抑制hPBMC表面结合和内化CpG-SODN,并抑制CpGSODN刺激的hPBMC TLR9 mRNA的表达及NF-xB的活化。同时CpG-N0DN还可有效的降低由于细菌DNA导致的小鼠死亡,并降低小鼠小鼠血清TNF-α水平。结论:成功筛选出有效的CpG-NODN,该CpG-NODN对CpG-SODN活化hPBMC具有抑制作用,这种抑制作用可能与影响hPBMC表面结合和内化CpG-SODN,抑制TLR9表达,进而抑制NF-xB的活化有关。同时该CpG-NODN对脓毒症小鼠的具有保护作用。  相似文献   

10.
目的应用生物传感器跟踪检测技术从传统抗炎中药中筛选具有拮抗内毒素作用的中药,并对其进行活性物质含量排序。方法将lipid A包被于生物传感器的非衍生板,建立靶点,测定22种去鞣质后的中药水煎液与lipid A的亲和力;选择具有较高亲和力的药物与定量脂多糖(5ng/mL)于37℃混合孵育30min,再测定其与lipidA的亲和力,以评价药物水提液中活性物质的含量。结果22种中药均具有与lipidA较高的亲和力(大于100RU);侧柏叶、地骨皮、石榴皮等16种中药中与lipidA特异性结合的活性物质含量较高。结论应用生物传感器技术建立的筛选平台快速而客观,筛选出的16种中药均含有能与lipidA发生特异性结合作用的非鞣质类活性物质。  相似文献   

11.
12.
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   

13.
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   

14.
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16.
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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18.
This study explored gender-related symptoms and correlates of alcohol dependence in a crosssectional study of 150 men and 150 women with a lifetime diagnosis of alcohol use disorders (AUD). Participants were recruited in equal numbers from treatment settings, correctional centres and the general community. Standardized measures were used to determine participants' use of substances, history of psychiatric disorders and psychosocial stress, their sensation seeking and family history of substance use and mental health disorders. Multivariate analyses were used to detect patterns of variables associated with gender and the lifetime severity of AUD. Men had a longer history of severe AUD than women. Women had similar levels of alcohol dependence and medical and psychological sequelae as men, despite 6 fewer years of AUD. More women than men had a history of severe psychosocial stress, severe dependence on other substances and antecedent mental health problems, especially mood and anxiety disorders. There were differences in family history of alcohol-related problems approximating same-gender aggregation. The severity of a lifetime AUD was predicted by its earlier age at onset and the occurrence of other disorders, especially anxiety, among both men and women. The limitations in the generalizability of these findings due to sample idiosyncrasies are discussed.  相似文献   

19.
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   

20.
Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.  相似文献   

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