广西眼镜蛇毒细胞毒素的分离及对人鼻咽癌等细胞抑制作用的研究

目的探讨广西眼镜蛇毒细胞毒素对人鼻咽癌细胞(CNE)等多种癌细胞株的抑制作用.方法经Sephadex G-50,CM-Sepharose CL-6B层析法从广西眼镜蛇毒中分离纯化获得细胞毒素(CTX),采用MTT检测CTX 对癌细胞株体外培养抑制作用,探索量效时效关系.结果从广西眼镜蛇毒中分离到一种细胞毒素单一组分(CTX CM-5)对体外培养的人鼻咽癌细胞株(CNE)、淋巴瘤细胞株(YAC)、人宫颈癌细胞株(HELA)和卵巢癌细胞株(Ho8990)的抑制有明显的剂量依赖关系,作用48 h的IC50分别为1.84,0.75,1.84和2.59 mg·L-1;随作用时间的延长,CTX CM-5对CNE细胞株作用最为明显,作用3h和24 h的IC50分别为4.78和1.04 mg·L-1.结论 CTX CM-5对体外培养的癌细胞株有较强的抑制作用.     

广西眼镜蛇毒细胞毒素的分离及对人鼻咽癌等细胞抑制作用的研究

目的　探讨广西眼镜蛇毒细胞毒素对人鼻咽癌细胞(CNE)等多种癌细胞株的抑制作用。方法　经SephadexG 5 0 ,CM SepharoseCL 6B层析法从广西眼镜蛇毒中分离纯化获得细胞毒素 (CTX) ,采用MTT检测CTX对癌细胞株体外培养抑制作用 ,探索量效时效关系。结果　从广西眼镜蛇毒中分离到一种细胞毒素单一组分 (CTXCM 5 )对体外培养的人鼻咽癌细胞株 (CNE)、淋巴瘤细胞株 (YAC)、人宫颈癌细胞株 (HELA)和卵巢癌细胞株 (Ho8990 )的抑制有明显的剂量依赖关系 ,作用 48h的IC50 分别为 1 84,0 75 ,1 84和 2 5 9mg·L-1;随作用时间的延长 ,CTXCM 5对CNE细胞株作用最为明显 ,作用 3h和 2 4h的IC50 分别为 4 78和1 0 4mg·L-1。结论　CTXCM 5对体外培养的癌细胞株有较强的抑制作用。     

华钩藤钩茎对NO供体诱导的小脑颗粒细胞神经元死亡的抑制作用

伪金丝桃素(PH)和金丝桃素(H)是贯叶金丝桃 Hypericum perforatum 中的光敏性植物色素。H 对肿瘤细胞株有细胞毒活性及诱导其凋亡的作用。PH 在该植物中的含量高于 H,但其诱导细胞凋亡的作用未曾研究。作者比较了 PH 与 H 对体外培养的人 T-淋巴细胞性白血病细胞株 Jurkat 的光毒性及诱     

流式细胞检测高压CO2对胃癌MMP2和MMP9水平的影响

目的:探讨高压二氧化碳(CO2)对胃癌细胞腹腔侵袭转移能力的影响.方法:体外培养高侵袭力人胃癌MKN45细胞株,在高压CO2(25 mmHg)及不同持续时间(1、2、3 h)干预后,应用流式细胞技术,检测其MMP2和MMP9的表达水平变化.结果:高压CO2作用后胃癌MKN45细胞株MMP2和MMP9蛋白表达有所变化.与常规细胞培养比较,MMP2和MMP9表达差异较为明显(P＜0.001,P＜0.01).结论:CO2对胃癌细胞的侵袭能力会产生一定的影响,高压CO2环境对胃癌细胞的侵袭能力影响较大.     

流式细胞检测高压CO2对胃癌MMP2和MMP9水平的影响

目的:探讨高压二氧化碳(CO2)对胃癌细胞腹腔侵袭转移能力的影响.方法:体外培养高侵袭力人胃癌MKN45细胞株,在高压CO2(25 mmHg)及不同持续时间(1、2、3 h)干预后,应用流式细胞技术,检测其MMP2和MMP9的表达水平变化.结果:高压CO2作用后胃癌MKN45细胞株MMP2和MMP9蛋白表达有所变化.与常规细胞培养比较,MMP2和MMP9表达差异较为明显(P＜0.001,P＜0.01).结论:CO2对胃癌细胞的侵袭能力会产生一定的影响,高压CO2环境对胃癌细胞的侵袭能力影响较大.     

吡哆醇对小鼠肝癌细胞H22体外抑制作用的研究

目的研究吡哆醇对体外培养小鼠肝细胞H22的细胞毒作用.方法应用MTT法,测定吡哆醇在不同浓度及不同作用时间对小鼠肝癌细胞的抑制作用.结果同阴性对照组相比,吡哆醇浓度为3 mmol/L时对肝癌细胞有轻度抑制作用(R=36.8%),6mmol/L时为高度抑制(IR=55.6%,P＜0.01).回归分析显示,IR%与给药浓度和作用时间呈正相关,尤以48小时为显著,呈线性趋势(r=0.9764,P＜0.01),其相应的IC50=5mmol/L.结论吡哆醇对体外培养的H22小鼠肝癌细胞系的生长具有抑制作用,且二者之间有剂量-效应关系和时间-效应趋势.     

马尾松树皮提取物对人体外癌细胞的广谱作用研究

目的：研究马尾松树皮提取物(Pinus massoniana bark extract，PMBE)对体外培养人癌细胞株的作用及其广谱性；方法：用四甲基偶氮唑蓝比色法(measurement of trititaed thymidine incorporation,MTT)，经四氮唑蓝染色测定PMBE处理前、后体外培养人癌细胞吸光度值的变化，评估其对不同癌细胞株的体外作用；结果：马尾松树皮提取物对体外培养的人癌细胞有广谱抑制作用，但不同癌细胞对其有不同程度的浓度或剂量依赖性；结论：马尾松树皮提取物可用于抗癌药物的筛选和研发。     

丙戊酸对人脑胶质母细胞瘤细胞株抑制增殖及诱导凋亡作用研究

目的研究丙戊酸(2-propylpentanoic acid,VPA)体外对人脑胶质母细胞瘤细胞株增殖抑制、诱导细胞周期阻滞及促进凋亡的作用,为临床治疗提供理论依据。方法 MTT比色法检测VPA对胶质母细胞瘤细胞株的杀伤作用;流式细胞术检测其对细胞周期及凋亡的影响作用;Western blot法检测乙酰化组蛋白H3(acetyl-Histone H3)、乙酰化组蛋白H4(acetyl-histone H4)表达量变化情况。结果 VPA对胶质瘤母细胞瘤细胞株SF295、U87具有抑制增殖作用,诱导细胞周期阻滞于G2/M期,乙酰化组蛋白H3、H4表达量呈时间依赖性增加。大剂量可以诱导出现凋亡。结论 VPA能够在体外抑制胶质瘤细胞生长,诱导细胞周期阻滞及促进细胞凋亡,其机制可能与促进组蛋白乙酰化有关。     

中华眼镜蛇细胞毒素及其偶联膀胱癌单克隆抗体的体外抑制膀胱癌细胞增殖的实验研究

目的从中华眼镜蛇的四种细胞毒素(cytotoxins,CTXs)中筛选活性最强的一种与膀胱癌单克隆抗体构建成免疫毒素(immunotoxin IT),并研究IT的体外抑制膀胱癌细胞增殖的活性。方法[3H]-TdR掺入法检测CTXs对膀胱癌细胞株的抑制增殖作用,用双功能偶联剂将CTX-12与BDI-1连接成IT,并用SDS-聚丙烯酰胺凝胶电泳、DAB染色法和[3H]-TdR掺入法鉴定和检测IT的活性。结果四种CTXs对BIU-87和EJ细胞株均有抑制增殖的活性,CTX-12与BDI-1能够连接成IT,IT对BIU-87和EJ细胞株具有特异性结合性。且IT仍具有抑制肿瘤细胞增殖的活性,其BIU-87,EJ和Lovo细胞作用6h的IC50分别为97.12,85.28和193.4mg/L,而作用半小时更换培养液培养至6h的IC50分别为94.64,81.28和865mg/L。结论四种CTXs对膀胱癌细胞株均有抑制增殖的活性,CTX-12与BDI-1连接的IT具有特异性抑制增殖的活性,IT和四种CTXs都有潜力成为新的抗膀胱癌药物。     

DHA复合物抑癌作用的实验研究

目的 :研究DHA复合物的抑癌作用。方法 :以昆明小鼠为荷瘤鼠研究DHA复合物对H2 2 、S180 、艾氏腹水瘤 3株癌细胞的抑制作用 ;用MTT法研究了DHA复合物在体外对U2 51、SKOV 3、SGC 3种癌细胞的半数肿瘤抑制浓度 (IC50 )。结果 :DHA复合物对H2 2 、S180 、艾氏腹水瘤均有明显的抑制作用 ,抑制率均大于30 % ,且具有显著性差异 (P <0 .0 5 )。DHA复合物在体外对U2 51、SKOV 3、SGC 3种癌细胞IC50 分别为 1.2 8,1.0 2 ,1.39均小于 10mg·L- 1。结论 :DHA复合物在体内和体外对癌细胞均有抑制作用     

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.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

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.     

Steroidal sapogenin contents in some domestic plants

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.     

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.