普罗托品对家兔血小板功能的影响

普罗托品(protopine,Pro)体外(1—1000μmol·L~(-1))和体内(10和20mg·kg~(-1))均抑制ADP,胶原,花生四烯酸(AA)和烙铁头蛇毒血小板聚集素(TMVA)诱导的兔血小板聚集及血小板5-HT释放。Pro不抑制AA诱导的免血小板TXA_2生成。也不升高血小板内cAMP水平,但升高cGMP水平。提示其抗血小板作用的机制与升高血小板内cGMP水平,抑制血小板释放活性物质有关。     

双苯氟嗪对血小板聚集和血栓形成的影响(英文)

在体内外实验中观察我国首创合成的新钙拮抗剂双苯氟嗪(Dip)对血小板聚集和实验性血栓形成的作用。Dip iv 1—2mg·kg~(-1)和1—100μmol·L~(-1)体外温育可剂量或浓度依赖性地抑制ADP和AA诱发的家兔血小板聚集。Dip iv 2.5—10 mg·kg~(-1)和ip 50—100 mg·kg~(-1)可抑制大鼠体内血栓形成;Dip iv 10mg·kg~(-1)和200μmol·L~(-1)体外给药可抑制体外血栓形成。提示,减轻紊乱的血小板与血管壁反应是其抗血栓作用的主要因素,Dip的作用强于Cin。     

祛栓灵胶囊抑制动物血小板聚集功能的研究

目的观察祛栓灵胶囊对动物血小板聚集功能的影响。方法采用ADP、凝血酶和花生四烯酸三种诱导剂,测定正常大鼠和血瘀模型兔服用祛栓灵胶囊7d后的血小板聚集性变化。结果大鼠服用祛栓灵胶囊62．5～250mg·kg^-1 7d后,对ADP和凝血酶诱导的血小板最大聚集率分别可抑制13．8％～24．0％和11．6％～35．3％;血瘀模型兔服用祛栓灵胶囊37．5～150mg·kg^-1 7d后,对ADP和凝血酶诱导的血小板最大聚集率分别可抑制22．1％～33．9％和16．3％～23．6％。但正常大鼠和血瘀模型兔服用祛栓灵胶囊后,对花生四烯酸诱导的血小板聚集均未见有明显影响。结论祛栓灵胶囊可明显抑制大鼠和兔体内由ADP和凝血酶介导的血小板聚集。     

玉米须水提物对自发性高血压大鼠血小板聚集功能的影响

目的研究玉米须水提物(AECS)对自发性高血压大鼠血小板聚集功能的影响和机制。方法自发性高血压大鼠随机分为模型组、AECS 5和15 g·kg~(-1)组,WKY大鼠作为正常对照组,各组灌胃给药,连续25 d。第25天取大鼠肝素抗凝血制备富血小板血浆,比浊法检测ADP和胶原诱导的血小板最大聚集率变化,并测定血浆总抗氧化能力、谷胱甘肽和血管紧张素Ⅱ水平。结果与WKY组比较,模型组大鼠ADP(3和10μmol·L~(-1))和胶原(4μg·mL~(-1))诱导的血小板最大聚集率增高,血浆总抗氧化能力和谷胱甘肽水平降低,血管紧张素Ⅱ水平增高;与模型组比较,AECS 5和15 g·kg~(-1)组大鼠在上述浓度ADP和胶原诱导的血小板最大聚集率降低,血浆总抗氧化能力和谷胱甘肽水平增高,血管紧张素Ⅱ水平下降。结论玉米须水提物可抑制自发性高血压大鼠的血小板聚集功能,机制与降低血管紧张素Ⅱ水平和抗氧化应激有关。     

心脉康胶囊对家兔血小板聚集的影响

目的研究心脉康胶囊对二磷酸腺苷(ADP)、花生四烯酸(AA)、血小板活化因子(PAF)诱导兔血小板聚集的影响。方法采用Born法,检测不同条件下ADP、AA、PAF诱导的兔血小板聚集率。结果与空白对照组比较,2 g.kg-1心脉康胶囊组能显著抑制ADP、AA、PAF诱导的兔血小板聚集率(P<0.01),1 g.kg-1心脉康胶囊组能显著抑制ADP、PAF诱导的兔血小板聚集率(P<0.01)。结论心脉康胶囊能抑制兔血小板聚集率。     

BM—13505抗栓作用及机理研究

BM 13505是新合成的血栓烷受体拮抗剂，BM 13505 0.45和0.23mg/kg iv延长大鼠颈动脉血管阻塞时间（P＜0.001和P＜0.01）。BM 13505 2mg/kg iv有效地防止AA 4mg/kg所致的大鼠脑血栓形成（P＜0.01）。BM 13505 10mg/kg ip可防止AA诱导的小鼠肺部栓塞（P＜0.01）。该药可延长小鼠尾出血时间。BM 13505显著抑制AA诱导的兔血小板聚集，半数抑制浓度IC50为0.17μmol/L，对ADP和胶原诱导的血小板聚集无影响。BM13505降低兔血小板及小鼠血浆中TXB2水平，对血小板cAMP水平无影响，在不远的将来，BM13505可能会发展成一种理想的抗血小板药及抗血栓药。     

异莲心碱抗血小板聚集和抗凝血作用

目的:探讨异莲心碱(isoliensinineI,L)对大鼠体内血小板聚集和凝血功能的影响。方法:以二磷酸腺苷(ADP)诱导血小板聚集,采用比浊法观察IL对兔体内外血小板13,5,min聚集率和最大聚集率的影响,同时评价IL对大鼠凝血酶原时间(PT)、活化部分凝血激酶时间(APTT)及凝血酶时间(TT)的影响。结果:IL 4 mg.L-1和8 mg.L-1能显著抑制ADP诱导的兔体外血小板13,5,min聚集率和最大聚集率,其抑制率为14.4%和27.9%;IL 5 mg.kg-1和10 mg.kg-1能显著抑制ADP诱导的兔体内血小板1,35,min聚集率和最大聚集率,其抑制率为20.0%和32.6%;IL能显著延长大鼠PT、APTT和TT。结论:IL具有对抗血小板聚集和凝血作用。     

白藜芦醇对高脂血症大鼠血小板聚集的影响及其机制研究

目的:研究白藜芦醇对高脂血症大鼠血小板聚集的影响及其可能机制.方法:建立大鼠的高脂血症模型,同时连续i.g.给予白藜芦醇(50mg· kg-1·d-1)或空白溶媒30 d,测定大鼠血浆TC、TG、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、丙二醛(MDA)、超氧化物歧化酶(SOD)、NO、内皮一氧化氮合酶(eNOS)、p-选择蛋白、血栓烷B2 (TXB2)和6-酮-前列腺素F1α(6-Keto-PGF1α),ADP诱导的血小板5 min最大聚集率.结果:与高脂模型组比较,高脂饲料白藜芦醇组大鼠在连续i.g.给予白藜芦醇(50 mg·kg-1·d-1)30 d后,大鼠血浆TG、TC、LDL-C含量均下降,分别下降19％、31％、51％,HDL-C含量增加1.33倍;SOD和eNOS活力升高,NO和6-Keto-PGF1α含量增加,MDA、p-选择蛋白、TXB2含量降低,ADP诱导的血小板5 min最大聚集率降低.结论:白藜芦醇能有效降低血小板聚集,可能是通过降低血脂水平,防止脂质过氧化和保护内皮细胞完整,影响NO合成,维持血浆或组织中的TXA2和PGI2平衡及细胞内外的钙离子平衡等多环节来发挥作用.     

六肽对兔血小板聚集活性的影响

目的研究六肽对兔血小板聚集活性的影响。方法采集健康家兔颈动脉血,以枸橼酸钠抗凝,用比浊法测其血小板在不同诱导剂诱导下聚集率。结果 1×10 5mol.L 1六肽,对兔ADP、花生四烯酸(AA)和凝血酶诱导的血小板聚集的抑制率分别为(66.22±1.40)%,(67.94±2.32)%和(58.18±4.67)%。六肽抑制兔ADP、AA和凝血酶诱导的血小板聚集的IC50分别为3.24×10 6mol.L 1,1.32×10 6mol.L 1和7.24×10 6mol.L 1。结论六肽在体外具有抑制兔血小板聚集的作用。     

替米沙坦对血小板聚集功能影响的体外实验研究

目的观察替米沙坦对血小板聚集功能的影响,探讨替米沙坦抑制血小板聚集的机制。方法采用比浊法测定不同浓度替米沙坦对二磷酸腺苷(ADP)、胶原(COLL)、花生四烯酸(AA)、肾上腺素(EPI)诱导的兔血小板聚集反应抑制情况,并与阿司匹林组对比。结果替米沙坦对ADP、COLL、AA、EPI诱导的血小板聚集均具有浓度依赖性抑制;10-5mol/L替米沙坦和3×10-4mol/L阿司匹林对四种诱导物的抑制率(%)是32.9、20.6、59.1、19.7及36.2、27.7、61.9、26.8,二者无显著性差异(P>0.05)。结论替米沙坦能抑制ADP、COLL、AA、EPI诱导的血小板聚集反应。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

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.

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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.

     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

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.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

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.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

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.     

Glycofection: The Ubiquitous Roles of Sugar Bound on Glycoplexes

Glycofection (transfection by using sugar-substituted polylysine) was assessed in order to provide an alternative to viral vectors for the transfer of genes into vascular smooth muscle cells. A rabbit vascular smooth muscle cell line (Rb-1 cells) was selectively transfected by using glycoplexes (glycosylated polylysine/pSV2LUC complexes) in the presence of 10 mu M of the fusogenic peptide GALA. A sugar-specific transfection was obtained when the glycofection was conducted for 1 h with glycoplexes containing either alpha Gal, alpha -Glc, alpha -GalNAc, beta -GlcNAc, or beta -GalNAc residues. The gene expression was high after transfection, with glycoplexes bearing alpha Gal, alpha -GalNAc, or beta -GalNAc residues that were weakly internalized, and low with glycoplexes carrying Lact or Rha residues that were well taken up by cells. These results suggest that 1) glycofection can be a good approach for a selective transfer of genes intovascular smooth muscle cells, 2) an efficient uptake of the glycoplexes is not the unique limiting step for an efficient transfection, and 3) the sugar-dependent trafficking of the glycoplexes inside the cells may account for the transfection efficiency.     

直肠癌下切缘病理组织学分析

目的探讨直肠癌逆向浸润与下切缘的安全距离的关系。方法对36例直肠癌Miles手术和Dixon手术后标本的肿瘤下缘1.0cm、2.0cm、3.0cm的肠壁及对应的系膜病理组织学检查,观察直肠癌逆向浸润或转移的距离。结果36例直肠癌标本距癌肿下缘1.0 cm、2.0cm、3.0cm的肠壁及对应的系膜病理组织学检查均为阴性,结论直肠癌远恻逆向浸润或转移未见超过1.0cm,因此认为保肛手术时切除肿瘤远侧肠管(包括系膜)2.0cm是安全的。