替尼泊苷多层包衣白蛋白纳米粒的制备工艺及体外抗肿瘤活性

目的以人血清白蛋白为载体包载替尼泊苷,经过包衣修饰后制备包载替尼泊苷的多层包衣纳米粒(teniposide-encapsulated multilayer nanoparticles,P-CS-NP),以期降低药物的不良反应并改善其体外抗肿瘤活性。方法以粒径、多分散指数和载药率为评价指标,采用单一因素法筛选出替尼泊苷白蛋白纳米粒的最优处方工艺,通过加入壳聚糖和聚谷氨酸聚乙二醇共聚物进一步制备多层包衣白蛋白纳米粒,筛选得到最优包衣量。以游离的替尼泊苷作为参比,用MTT法测定纳米粒对人肺癌A549细胞的体外细胞毒性,并用流式细胞仪和共聚焦显微镜测定和观察多层包衣纳米粒的细胞摄取率和细胞摄取行为。结果确定了多层包衣纳米粒的处方及制备工艺。多层包衣纳米粒的体外细胞毒性比游离的替尼泊苷小,摄取具有时间依赖性,与壳聚糖共孵育的纳米粒的细胞摄取量增加,入胞后纳米粒主要分布在细胞质。结论白蛋白纳米粒能被壳聚糖和聚谷氨酸聚乙二醇共聚物包衣修饰,多层包衣纳米粒可以作为替尼泊苷的药物递送载体,其体外细胞毒性降低。     

苯妥英钠对化学治疗耐药胶质瘤细胞内卡莫司汀和替尼泊苷药物浓度的影响

目的 研究苯妥英钠对化学治疗耐药人胶质母细胞瘤细胞(8-MG-BA)内卡莫司汀、替尼泊苷积聚浓度的影响.方法 实验细胞分为5组,H4细胞组、8-MG-BA细胞组、8-MG-BA+苯妥英钠5 mg,/L组、8-MG-BA+苯妥英钠10 mg/L组、8-MG-BA+维拉帕米5 mg/L组.采用高效液相色谱法(HPLC)检测各组细胞内卡莫司汀、替尼泊苷积聚浓度.采用外标标准曲线法,以药物的质量浓度(C)为横坐标、峰面积(A)为纵坐标进行线性回归计算,并测定仪器精密度与方法回收率.结果 吸收1、3h后,H4细胞组细胞内卡莫司汀、替尼泊苷含量均高于8-MG-BA细胞组[吸收1h后卡莫司汀浓度:(1.75±0.05)mg/L比(0.31±0.03)mg/L,吸收3h后卡莫司汀浓度:(1.70±0.03)mg/L比(0.39±0.04)mg/L,吸收1h后替尼泊苷浓度:(1.18±0.03)mg/L比(0.42±0.03)mg/L,吸收3h后替尼泊苷浓度:(1.09±0.04)mg/L比(0.46±0.03)mg/L,均P＜0.01];8-MG-BA+维拉帕米5 mg/L组、8-MG-BA+苯妥英钠5 mg/L组、8-MG-BA+苯妥英钠10 mg/L组细胞内卡莫司汀、替尼泊苷含量均高于8-MG-BA细胞组[吸收1h后卡莫司汀浓度:(0.56±0.04)mg/L、(1.10±0.12)mg/L、(1.37±0.04)mg/L比(0.31±0.03)mg/L,吸收3h后卡莫司汀浓度:(0.68±0.04)mg/L、(1.25±0.03)mg/L,(1.49±0.04)mg/L比(0.39±0.04)mg/L,吸收1h后替尼泊苷浓度:(0.50±0.03)mg/L、(0.59±0.03)mg/L、(0.95±0.04)mg/L比(0.42±0.03)mg/L,吸收3h后替尼泊苷浓度:(0.53±0.04)mg/L、(0.62±0.04)mg/L、(1.01±0.03)mg/L比(0.46±0.03)mg/L,均p＜0.01];8-MG-BA+苯妥英钠5 mg/L组、8-MG-BA+苯妥英钠10 mg/L组细胞内卡莫司汀、替尼泊苷含量均高于8-MG-BA+维拉帕米5 mg/L组(P＜0.01);8-MG-BA+苯妥英钠5 mg/L组细胞内卡莫司汀、替尼泊苷含量均低于8-MG-BA+苯妥英钠10 mg/L组(P＜0.05).当被测VM26及卡莫司汀质量浓度为0.05～5 mg/L时,其浓度与峰面积之间具有良好的线性关系.替尼泊苷回收率分别为(96±5)％、(100±4)％和(99±2)％;卡莫司汀回收率分别为(100±5)％、(99±4)％和(99±4)％,日内(24h)、日间(2d间)误差相对标准偏差分别为4.47％和4.96％(n=5).结论 苯妥英钠可以增加化学治疗耐药8-MG-BA细胞内卡莫司汀、替尼泊苷的积聚浓度,并与剂量有关.     

替尼泊苷方案治疗急性非淋巴细胞白血病疗效分析

替尼泊苷方案为国产替尼泊苷(VM-26)联合DA(柔红霉素、阿糖胞苷).我院采用该方案治疗成人急性非淋巴细胞白血病(ANLL),取得较好疗效,报告如下.     

HPLC法测定大鼠血浆中替尼泊苷浓度

目的建立大鼠血浆中替尼泊苷的HPLC方法。方法采用HPLC法,使用反相C_(18)柱(250mm×4.60mm,5μm,Phe- nomenex),流动相为甲醇:水:醋酸(38:60:2,V/V),流速为1.0 mL·min~(-1),检测波长230nm。结果替尼泊苷为0.5～25.0mg·L~(-1)时呈线性关系(r=0.9999),血浆检测限为0.06mg·L~(-1)。日内、日间RSD均<5%。给药后30min血浆的质量浓度为(4.21±0.37)mg·L~(-1)(n=4)。结论本方法简便、灵敏,可用于体内测定替尼泊苷。     

替尼泊苷长循环阳离子脂质体的制备

目的优化薄膜分散法制备替尼泊苷长循环阳离子脂质体的最佳处方。方法薄膜分散法制备脂质体,以粒径和包封率为考察指标,用单因素考察和正交设计等方法优化脂质体的处方。结果优化后的最佳处方为:磷脂DSPC和PEG 5 000-DOTMA比为4∶1,药物和磷脂比为1∶4,磷脂与胆固醇比为2∶1,乳化剂为卵磷脂。优化的脂质体平均粒径为115.45nm,平均Zeta电位为25.54mV,平均包封率为91.32%,5±3℃放置180d和25±2℃放置30d各项指标变化不显著。结论制备的替尼泊苷长循环阳离子脂质体包封率高,粒径小,释放缓慢,稳定性和安全性好。     

替尼泊苷磷脂复合物白蛋白纳米粒的制备与表征

目的 制备替尼泊苷磷脂复合物白蛋白纳米粒,并表征其理化性质.方法 以人血清白蛋白和蛋黄卵磷脂E80为辅料,替尼泊苷为主药,采用超声法制备替尼泊苷磷脂复合物白蛋白纳米粒及其冻干制剂.以粒径和多分散系数(PDI)为主要考察指标来优化纳米粒的处方及制备工艺;用激光粒度分析仪和透射电镜对其形态和结构进行表征;用葡聚糖凝胶柱法测定纳米粒的包封率和载药量.结果 成功制备了替尼泊苷磷脂复合物白蛋白纳米粒,平均粒径为182.3 ±11.7 nm,PDI为0.168 ±0.02,Zeta电位为-10.75±1.42 mV,包封率为82.27％±2.74％,载药量为4.29％±0.11％;冻干制剂的外观良好,复溶后的粒径和PDI均符合要求.结论 所用方法简单新颖,具有较好的应用前景.     

沙利度胺联合替尼泊苷对人胃腺癌移植瘤生长的影响

目的探讨沙利度胺联合替尼泊苷在对胃腺癌BGC-823裸鼠移植瘤生长及肿瘤细胞周期的影响,了解二者联合对移植瘤的抑制作用。方法建立人胃腺癌BGC823移植瘤模型,实验分组,计算抑瘤率,流式细胞仪检测肿瘤细胞生长周期及凋亡情况。结果沙利度胺联合替尼泊苷组肿瘤组织S期细胞比例明显下降,大量肿瘤细胞阻滞于G2/M期,并可见明显凋亡峰。结论替尼泊苷联合沙利度胺对抑制人胃腺癌BGC823细胞生长具有协同作用,可诱导肿瘤细胞凋亡。     

替尼泊苷注射液致过敏性休克

患儿男,4.5岁,因急性淋巴细胞白血病缓解1月余,于2004年12月31日入院接受强化治疗。入院后分别给予替尼泊苷(卫萌)、阿糖胞苷(赛得萨)静脉滴注。当阿糖胞苷滴注完毕更换为替尼泊苷后静滴3～5min时,患儿出现双足痉挛、腹痛、呕吐,并可见全身红色皮疹,进行性加重,面色青灰,四肢肌张力下降,大小便失禁,呼吸减弱,全身皮肤青紫,考虑为替尼泊苷所致速发型过敏性休克。给予盐酸肾上腺素0.5mg静脉注射,地塞米松5mg静脉滴注,盐酸异丙嗪12.5mg肌肉注射,吸氧,并拍背、心脏按压后面色青紫好转,但四肢末梢仍冰凉、青紫。查体:HR:170～180次/min,BP50/30…     

替尼泊苷自微乳的处方筛选及体外评价

目的筛选替尼泊苷自微乳的最优处方,并对其进行体外评价。方法通过溶解度实验、伪三元相图的绘制、粒径考察筛选出最优处方;以替尼泊苷混悬液为对比,测定替尼泊苷自微乳在不同溶出介质中的溶出度;考察替尼泊苷自微乳的稳定性。结果实验筛选得到的最优处方为油酸乙酯∶Cremopher ELP∶异丙醇=20∶60∶20,载药量1.5%。在不同溶出介质中,替尼泊苷释药2h后的累积释药量均可达90%以上,且3h后的累积释药量接近100%。稳定性实验结果表明替尼泊苷自微乳在40℃、25℃和冷热循环条件下是稳定的。结论实验制得替尼泊苷自微乳具有较好的溶解度,在不同溶出介质中有较高溶出度,稳定性良好。     

硼替佐米联合5-杂氮胞苷抑制JAK/STAT信号通路对T细胞淋巴瘤细胞增殖和凋亡的影响北大核心CSCD

目的研究硼替佐米联合5-杂氮胞苷对T细胞淋巴瘤细胞增殖、凋亡及机制。方法对照组Jurkat细胞以3μmol·L^(-1)5-杂氮胞苷处理,低、中、高剂量实验组以10,30,50 nmol·L-1的硼替佐米+3μmol·L^(-1)5-杂氮胞苷处理,空白组加等量生理盐水。用噻唑蓝(MTT)法及流式细胞术检测细胞增殖、凋亡,用蛋白免疫印迹法检测细胞JAK/STAT信号通路蛋白表达。结果干预72h后,对照组和低、中、高剂量实验组细胞增殖抑制率分别为(39.05±2.63)%,(31.26±2.43)%,(60.12±3.05)%,(72.16±3.64)%。干预24,48,72 h后,中、高剂量实验组细胞增殖抑制率均高于对照组,且随硼替佐米浓度增大及作用时间延长逐渐升高(P<0.05)。干预48 h后,对照组和低、中、高剂量实验组细胞凋亡率均显著高于空白组。对照组和低、中、高剂量实验组细胞增殖指数低于空白组,凋亡率高于空白组(均P<0.05);且实验组增殖指数均低于对照组,细胞凋亡率均高于对照组(均P<0.05)。空白组、对照组和低、中、高剂量实验组Janus激酶1(JAK1)蛋白相对表达量为2.68±0.22,2.15±0.31,1.82±0.25,1.53±0.15,0.89±0.14,TYK2蛋白相对表达量为3.84±0.56,2.25±0.46,2.37±0.39,2.26±0.33,1.28±0.26;对照组和低、中、高剂量实验组Janus激酶1(JAK1)、TYK2蛋白相对表达量均低于空白组(均P<0.05),低、中、高剂量实验组JAK1蛋白及高剂量实验组TYK2蛋白相对表达量低于对照组(均P<0.05)。结论硼替佐米可协同增强5-杂氮胞苷抑制T细胞淋巴瘤细胞的增殖,并促其凋亡,其作用机制与显著抑制JAK/STAT信号通路中蛋白表达有关。     

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.     

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.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

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.     

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.