忆美尔颗粒对小白鼠学习记忆障碍的药效学

目的:探讨忆美尔颗粒对学习记忆等脑功能的改善作用.方法:采用氢溴酸东莨菪碱致小鼠记忆获得障碍模型,氯霉素致小鼠记忆巩固障碍模型和40%乙醇致小鼠记忆再现障碍模型,用跳台法,Y-型电迷路法评价忆美尔颗粒对小鼠记忆能力的影响.结果:忆美尔颗粒能拮抗化学药物所致小鼠记忆障碍.结论:忆美尔颗粒具有益智功能和改善学习记忆能力作用.     

葛根素对β-淀粉样肽所致痴呆模型小鼠学习记忆的影响

目的 :研究葛根素对 β 淀粉样肽所致痴呆模型小鼠学习记忆障碍的影响。方法 :以 β 淀粉样肽3μl(1mmol·L-1)icv制备小鼠学习记忆障碍模型 ,用Morris水迷宫法检测小鼠学习记忆能力。同时检测脑中及血中超氧化歧化酶 (SOD)、丙二酰醛(MDA)含量。结果 :葛根素 2 5和 5 0mg·kg-1均能改善模型小鼠的学习记忆 (P <0 .0 5或P <0 .0 1)。生化指标测定显示葛根素能使模型小鼠脑及血中的SOD增多、MDA减少 (P <0 .0 5或P <0 .0 1)。结论 :葛根素可对抗 β 淀粉样肽的神经毒性 ,其机制可能与清除脑自由基及提高抗氧化活性作用有关     

脑益康对阿尔茨海默病模型小鼠学习记忆的影响

目的 :观察脑益康对阿尔茨海默病 (Alzhei mer’sdisease ,AD)模型小鼠学习记忆的影响 ,并探讨其改善学习记忆的机制。方法 :采用D 半乳糖 (D Gal)和亚硝酸钠 (NaNO2 )腹腔注射建立小鼠AD模型 ,通过迷宫刺激器和水迷宫实验检测小鼠学习记忆能力 ;生化方法检测小鼠脑组织内超氧化物歧化酶 (SOD)活性和丙二醛 (MDA)含量 ;透射电镜观察小鼠海马神经细胞的超微结构。结果 :模型对照组小鼠学习记忆能力下降 ,SOD活性降低 ,MDA含量升高 ;而与模型对照组比较 ,脑益康小、中、大剂量组(2 .4、7.2、2 4g·kg-1·d-1)均可显著改善模型小鼠的学习记忆能力 ,提高脑内SOD活性 ,降低脑内MDA含量 (P <0 .0 1或P <0 .0 5 ) ,阻抑海马神经细胞的退行性变化。结论 :脑益康可改善D 半乳糖和亚硝酸钠所致AD模型小鼠的学习记忆能力。     

荨麻总黄酮对记忆障碍模型小鼠学习记忆能力的影响

目的 研究荨麻总黄酮(TUF)对记忆障碍模型小鼠学习记忆能力的影响.方法 预防性给予小鼠TUF后,用不同方法模拟小鼠记忆获得障碍模型,行八臂迷宫试验;通过小鼠体重变化、负重游泳试验及血清和脑中总抗氧化能力(T-AOC)和超氧化物歧化酶(SOD)水平的变化,评估TUF的抗衰老、抗氧化作用.结果 TUF可显著改善东莨菪碱、氯霉素、40％乙醇对小鼠记忆行为能力的影响;增强D-半乳糖致衰老模型小鼠的记忆力,维持正常增重及延长负重游泳时间,还可显著提高衰老小鼠的抗氧化能力.结论 TUF可有效改善记忆障碍模型小鼠的记忆力,这可能与其抗氧化能力有关.     

谷氨酰胺对铅致学习记忆减退小鼠学习记忆障碍的影响

目的探讨谷氨酰胺（Gln）对铅致学习记忆减退小鼠的学习记忆能力的效果。方法小鼠饮用0.1%醋酸铅溶液2个月,再分别给予补充1%、2%Gln的饲料喂养2周后,用穿梭、避暗等实验方法测定小鼠学习记忆能力,同时测定小鼠脑单胺氧化酶（MAO）和超氧化物歧化酶（SOD）。结果铅中毒小鼠记忆能力明显降低,表现为避暗实验潜伏期缩短,穿梭实验主动回避次数减少,谷氨酰胺各剂量组潜伏期延长,主动回避次数增加,同时脑MAO降低,脑SOD升高。结论谷氨酰胺对醋酸铅所致小鼠记忆障碍具有保护作用,能增强学习记忆能力。     

健脑合剂改善小鼠学习记忆作用及其机理初探

目的 :观察中药健脑合剂对记忆障碍小鼠学习记忆的影响 ,并初步探讨其作用机理。方法 :以跳台法、避暗法与电迷宫试验检测由东莨菪碱、亚硝酸钠及乙醇所致记忆障碍小鼠及D 半乳糖与三氯化铝模型小鼠的学习记忆能力 ,测定大脑胆碱酯酶活性、LPO含量与全血SOD活性。结果 :健脑合剂 1 4g·kg-1和 2 8g·kg-1可明显改善由东莨菪缄、亚硝酸钠及乙醇所致记忆获得、记忆巩固及记忆再现障碍 ,增强D 半乳糖模型小鼠与三氯化铝小鼠的被动学习能力 ,提高D 半乳糖所致衰老小鼠全血SOD活性及抑制脑LPO生成 ,显著降低痴呆小鼠脑胆碱酯酶活性。结论 :健脑合剂能提高记忆障碍模型小鼠及三氯化铝与D 半乳糖模型小鼠学习记忆功能 ,其机制可能与影响中枢M胆碱能系统和改善体内自由基平衡有关     

芹菜甲素对学习记忆障碍模型小鼠的作用

目的采用化学药物导致小鼠学习记忆能力下降的损伤模型,研究芹菜素的促智作用及其机理。方法用东莨菪碱致记忆获得障碍、亚硝酸钠和电休克致记忆巩固障碍、30%乙醇致记忆再现障碍三种模型小鼠为实验对象,以其学习记忆能力为指标,考察芹菜素的促智作用。结果芹菜素(10、20、40mg.kg-1,i.g),能明显对抗记忆获得、巩固和再现障碍模型小鼠学习记忆能力的下降。结论芹菜素能有效地促进记忆障碍模型小鼠的学习记忆能力。     

灯盏花素对动物学习记忆能力的影响

采用两种模型、两种方法观察灯盏花素对大鼠、小鼠学习、记忆能力的影响.结果表明灯盏花素能明显改善东莨菪碱所致的小鼠学习、记忆获得障碍(与模型组比较,P＜0.05),明显改善乙醇所致的大鼠、小鼠记忆再现障碍(与模型组比,均为P＜0.05),并使二者的学习能力明显加强(与生理盐水组比较,P＜0.05),与脑复素比较,作用相近或稍强.     

丹皮酚对APP/PS1阿尔茨海默病小鼠的治疗作用

目的 研究丹皮酚(paeonol,Pae)对APP/PS1小鼠学习记忆能力、淀粉样斑块沉积、脑内神经元异常活动和神经元凋亡的改善作用.方法 采用饮食中补充Pae(50 mg·kg-1·d-1)的饲养方案喂养APP/PS1小鼠3个月,通过水迷宫实验研究小鼠的学习记忆能力;通过脑电图记录研究小鼠神经元放电活动;通过硫代黄素...     

基于cAMP/CREB/BDNF信号通路探究活力滋源宝对D-半乳糖致衰老小鼠学习记忆的影响

目的：探究活力滋源宝对D-半乳糖致衰老小鼠学习记忆的保护作用及作用机制。方法：60只小鼠随机分为空白组、模型组、吡拉西坦阳性对照组（0.8 g·kg-1）、活力滋源宝低、中、高剂量组（0.3、0.6、1.2 g·kg-1）,利用皮下注射D-半乳糖复制衰老小鼠模型,通过避暗实验和Morris水迷宫实验测试小鼠的学习记忆能力,采用酶联免疫法（ELISA法）测定小鼠大脑中环磷酸腺苷（cAMP）、环磷腺苷效应元件结合蛋白（CREB）及脑源性神经营养因子（BDNF）水平的变化。结果：活力滋源宝低中高剂量组均能不同程度地延缓小鼠衰老,改善学习记忆障碍,提升大脑中cAMP、CREB和BDNF的含量。结论：活力滋源宝可通过调节c AMP/CREB/BDNF信号通路改善衰老小鼠的学习记忆障碍。     

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.