奥曲肽抑制前列腺癌药理作用与多药耐药机制的相关性研究

目的：探讨奥曲肽抑制前列腺癌生长的药理作用与多药耐药现象之间的相关性。方法：MTF比色分析法测定奥曲肽对人前列腺癌细胞株PC-3生长的影响;实时定量PCR法,分别检测PC-3细胞P糖蛋白（P-gp）和多药耐药相关蛋白（MRP）的mRNA水平。结果：1×10^-9～1×10^-6mol·L^-1的奥曲肽能呈浓度依赖性抑制PC-3细胞的增殖,同时下调MRPmRNA的表达水平。但PC-3细胞检测不到P-gPmRNA的表达。结论：奥曲肽抑制PC-3细胞的增殖可能与其抑制MRP-3的表达相关。     

三苯氧胺对前列腺癌细胞PC-3增殖抑制和诱导凋亡实验研究

目的探讨三苯氧胺（TAM）抑制前列腺癌细胞PC-3增殖以及诱导凋亡的机制。方法不同浓度三苯氧胺干预细胞,通过四氮唑蓝比色法（MTT）、原位细胞凋亡检测（TUNEL）以及流式细胞术等方法检测TAM增殖抑制及诱导凋亡作用。结果 MTT法以及TUNEL法显示0、10-6mol/L TAM对前列腺癌细胞PC-3的生长无明显抑制作用,10-5、10-4、10-3mol/L TAM有显著的抑制增殖及诱导凋亡的作用（P〈0.05）;流式细胞术检测其活化caspase-3的表达情况显示10-4、10-3mol/L TAM活化caspase-3表达显著增高（P〈0.05）。结论 TAM能抑制前列腺癌细胞PC-3增殖和诱导其凋亡,作用呈剂量和时间依赖性,其机制可能通过诱导caspase-3表达活化增强,最终导致细胞凋亡。     

血管内皮生长因子反义寡核苷核对前列腺癌细胞PC3生长特性的影响

目的探讨血管内皮生长因子(VEGF)反义寡核苷核对前列腺癌细胞PC3生长特性的影响。方法采用新型脂质体Oligofectamine携带VEGF反义寡核苷酸转染激素非依赖性前列腺癌细胞PC3,实验分为对照组、反义寡核苷核苷酸组和正义寡核苷酸组。Western Blot杂交的方法检测细胞VEGF蛋白的表达,四甲基偶氮唑蓝法(MTT)检测细胞增殖变化,流式细胞仪检测细胞凋亡情况。结果新型脂质体可以携带VEGF反义寡核苷酸转染前列腺癌细胞PC3,与对照组和正义寡核苷酸组比较,反义寡核苷酸组细胞VEGF蛋白的表达明显下降,增殖受到明显抑制,凋亡率增加。结论新型脂质体Oligofectamine可以携带VEGF反义寡核苷酸成功转染前列腺癌细胞PC3,抑制VEGF的表达,进而抑制肿瘤细胞的增殖,促进其凋亡。     

苦参素对人前列腺癌PC-3细胞体外作用研究

目的探讨苦参素对人前列腺癌PC 3细胞的生长抑制作用及可能的作用机制。方法采用MTT法检测PC 3细胞的生长抑制率,流式细胞仪检测PC 3细胞周期改变,免疫组化法检测PC 3细胞中Bcl 2和Bax的表达。结果随着苦参素浓度的增加和作用时间的延长,PC 3细胞生长抑制率呈明显上升趋势(P＜0.05)。随着苦参素浓度的增加,G0/G1期和S期PC 3细胞所占比例逐渐上升,而G2/M期所占比例逐渐下降,同时Bcl 2表达下调,而Bax表达上调。结论苦参素能通过诱导人前列腺癌PC 3细胞周期阻滞于G0/G1和S期,下调Bcl 2表达和上调Bax的表达抑制癌细胞的生长增殖。     

微管稳定剂Taxol对缺氧心肌细胞Cx43蛋白的影响

目的观察微管稳定剂Taxol对缺氧心肌细胞Cx43表达和分布的影响,探讨其作为新的抗心律失常药物的潜在价值。方法酶解法分离的大鼠心肌细胞缺氧120 min,并以不同浓度的Taxol干预;台盼蓝排斥实验测定细胞存活率;免疫印迹检测Cx43的蛋白表达,免疫荧光染色后激光共聚焦显微镜观察分析Cx43的分布。结果 Taxol在0.1～10nmol·L-1浓度下成剂量依赖性地提高杆状细胞数,促进细胞存活,而100 nmol·L-1～10μmol·L-1浓度下杆状细胞数开始减少;缺氧时心肌细胞Cx43蛋白表达下降,Taxol呈剂量依赖性地改善心肌细胞的Cx43表达,但过量的Taxol则抑制心肌Cx43;正常心肌细胞Cx43主要分布在细胞两端,缺氧时细胞侧边出现Cx43分布。0.1～10nmol·L-1的Tax-ol呈剂量依赖性地抑制侧边Cx43,100 nmol·L-1～10μmol·L-1的Taxol也抑制心肌细胞两端Cx43。结论缺氧导致心肌细胞Cx43表达降低,分布紊乱,低剂量微管稳定剂Tax-ol可以明显地保护缺氧心肌Cx43,具有潜在的抗缺血性心律失常的临床应用价值。     

白藜芦醇通过上调TET1的表达抑制前列腺癌细胞系的迁移和侵袭

目的:研究白藜芦醇(Resveratrol,Res)对人前列腺癌细胞系PC3和DU145增殖、迁移和侵袭的影响及其作用机制.方法:不同浓度的Res处理前列腺癌细胞(PCa)系后,用细胞计数试剂盒(CCK-8)法验证Res对PCa细胞生长的抑制,实时定量聚合酶链式反应(qRT-PCR)检测Res对TET1表达的影响.采用...     

黄芪多糖对前列腺癌PC3细胞增殖和凋亡的影响

目的探讨黄芪多糖对前列腺癌细胞株PC3细胞增殖和凋亡的影响。方法分别用浓度为0.5、1、2.5、5、10 mg/ml的黄芪多糖(APS)干预PC3细胞12、24、36 h后,用甲基噻唑基四唑法检测不同浓度APS对PC3细胞增殖的量效和时效关系;台盼蓝染色法测定细胞生长曲线;APS干预24 h后流式细胞仪检测细胞凋亡率。结果 APS能抑制PC3细胞的增殖,呈时间与浓度依赖性,不同浓度APS组之间与不同作用时间组之间的差异均有统计学意义(P<0.05)。APS干预PC3细胞24 h后,对照组细胞凋亡率为5.01%,1 mg/ml和5 mg/ml的APS培养24 h细胞凋亡率分别为14.46%和27.71%,较对照组明显增加,且差异均具有统计学意义(P<0.05)。结论APS能够抑制前列腺癌细胞株PC3细胞的增殖,并诱导其凋亡。     

不同浓度七氟醚对人前列腺癌细胞增殖与侵袭能力的影响

目的 观察不同浓度七氟醚对人前列腺癌 PC3 细胞增殖与侵袭的影响。方法 将 PC3 细胞随机分为 4 组： 对照组、 Treat1 组、 Treat2 组和 Treat3 组。对照组仅通入 O2及 CO2, Treat1～3 组在此基础上经 1.7%、 3.4%、 5.1% 七氟醚分别作用 2、 4、 6 h。MTT 检测各组细胞的增殖能力; Transwell 法检测各组细胞的侵袭能力; Western blot 检测各组细胞中缺氧诱导因子-1α（HIF-1α）蛋白表达水平。结果 与处理前相比, 处理 2、 4 和 6 h 后, 人前列腺癌 PC3 细胞的增殖和侵袭能力均明显增强 （均 P＜0.05）, 细胞中 HIF-1α的蛋白表达水平明显上调 （P＜0.05）, 且 Treat3 组＞ Treat2 组＞Treat1 组（P＜0.05）。结论 七氟醚可增强人前列腺癌 PC3 细胞的增殖与侵袭能力, 且随着时间和浓度变化细胞的增殖与侵袭能力逐渐增强, 其机制可能与上调 HIF-1α的表达有关。     

人参皂苷Rg3差异调节前列腺癌细胞PC3和DU145增殖

目的 探讨人参皂苷Rg3对前列腺癌细胞PC3和DU145细胞增殖的调节作用。方法 100 µmol/L人参皂苷 Rg3处理体外培养的前列腺癌细胞 PC3和 DU145,使用 CCK-8实验检测细胞的增殖能力;DCFH-DA活性氧荧光探针试剂盒检测人参皂苷 Rg3处理的 DU145细胞中活性氧（ROS）水平;JC-1法检测 PC3和 DU145细胞线粒体膜电位的去极化;RT-PCR和免疫印迹法检测PC3和DU145细胞中氧化还原相关蛋白的表达差异。结果 CCK-8实验结果表明,100 µmol/L人参皂苷 Rg3能够显著抑制 PC3细胞增殖,而对 DU145细胞的增殖没有显著调节作用;DCFHDA活性氧荧光探针试剂盒检测结果表明,人参皂苷 Rg3能够显著上调 DU145细胞和 PC3细胞中 ROS水平;JC-1检测实验表明,人参皂苷Rg3能够诱导PC3和DU145细胞中线粒体膜电位去极化;RT-PCR和免疫印迹实验表明,抗氧化蛋白谷胱甘肽过氧化物酶-1（GPX-1）和超氧化物歧化酶2（SOD2）在DU145细胞中的表达显著高于PC3细胞。结论 人参皂苷Rg3对PC3和DU145细胞的增殖表现出不同的调节作用,可能与细胞中抗氧化蛋白的表达差异有关。     

蕃茄汁对人前列腺癌PC-3细胞增殖的影响

目的　研究番茄汁对人前列腺癌PC 3细胞增殖的影响及其可能的机制。方法　体外培养人前列腺癌PC 3细胞,分别加入不同浓度的番茄汁;用彗星试验测定经番茄汁处理的人前列腺癌PC 3细胞DNA链断裂情况,分析DNA的损伤作用;采用MTT法测定细胞的增殖情况。结果　番茄汁对人前列腺癌PC 3细胞的DNA具有损伤作用,可使DNA链断裂,DNA的迁移长度与彗星细胞拖尾率显著增高,与对照组相比,差异有非常显著性;能抑制PC 3细胞的增殖,与对照组相比,各实验组的吸光度逐渐降低,差异有非常显著性,且随着浓度的增加抑制作用逐渐加强。结论　番茄汁可诱导人前列腺癌PC 3细胞的DNA损伤,从而抑制其生长。     

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.