促大鼠骨髓间充质干细胞向神经元样细胞分化的研究

目的探讨成年大鼠骨髓间充质干细胞（BMSCs）的体外培养和向神经元样细胞分化的方法。方法通过梯度分离获得成年大鼠MSCs,在细胞因子和氧化剂作用下对其诱导分化为神经元样细胞,免疫细胞化学方法检测神经元特异性烯醇化酶（NSE）、神经丝蛋白（NF）、胶质纤维酸性蛋白（GFAP）和神经巢蛋白（Nestin）的表达情况,流式细胞仪检测分析诱导率。结果BMSCs被转化神经元样细胞并表达Nestin。应用碱性成纤维细胞生长因子（bFGF）、叔丁基对羟基茴香醚（BHA）所获得的神经元样细胞诱导率高（49.7%）。结论bFGF、BHA能促进大鼠骨髓间充质干细胞分化为神经元样细胞。     

人脂肪间充质干细胞体外定向诱导分化为胰岛样细胞的实验研究

目的体外定向诱导人脂肪间充质干细胞向胰岛样细胞的分化。方法人脂肪间充质干细胞分3个阶段进行诱导,第一阶段培养在含适当浓度的2-巯基乙醇的高糖-达氏修正依氏培养基(HG-DMEM)培养2d,第二阶段在含适当浓度的B27、碱性成纤维细胞生长因子(bFGF)及表皮生长因子(EGF)的HG-DMEM培养基中诱导6d,第三阶段在含适当浓度的2-巯基乙醇和B27和尼克酰胺高糖无血清DMEM培养基诱导细胞向胰岛样细胞分化。对照组用HG-DMEM培养。在相差显微镜下观察细胞的形态;用反转录-聚合酶链反应(RT-PCR)法检测诱导前后nestin、胰岛素基因的表达;用免疫荧光染色法检测诱导前后nestin、胰岛素的表达;诱导第三阶段进行双硫腙染色鉴定胰岛B样细胞团。结果未经诱导的脂肪间充质干细胞呈长梭形贴壁生长,诱导后细胞逐渐变圆,并聚集成团。诱导8d细胞nestin基因呈阳性表达,诱导14d细胞nestin基因表达量下降,胰岛素基因表达呈阳性。诱导后的细胞团双硫腙染色呈棕红色。结论2-巯基乙醇、EGF、bFGF及尼克酰胺等可在体外诱导人脂肪间充质干细胞分化为具有分泌胰岛素功能的胰岛样细胞。     

脂肪来源间充质干细胞与免疫调节因子间 作用的研究进展

间充质干细胞（MSCs）是中胚层中具有高度自我更新和多向分化潜能的非造血多能干细胞,可以分化为成 脂细胞、成骨细胞、成软骨细胞、肝细胞、心肌细胞、神经元干细胞、胰岛样细胞等。MSCs 具有免疫调节特性,可通过 分泌吲哚胺-2,3-双加氧酶（IDO）和前列腺素 E2（PGE2）来发挥免疫调节作用,同时又能在炎性因子如干扰素 γ （IFN-γ）的预刺激下增强其免疫调节功能。研究发现,在脂肪组织中存在丰富的,使 MSCs 成为成年干细胞非常有吸 引力的来源。本文对目前脂肪来源间充质干细胞（ADSCs）和以上 3 种免疫调节因子之间相互作用的研究进展作一 综述。     

丹参水煎液对BMSCs分化为神经元样细胞的诱导作用研究

目的：研究丹参水煎液诱导BMSCs分化为神经元样细胞的作用,探索提高MSCs向神经元样细胞分化的诱导条件。方法：全骨髓贴壁法分离大鼠BMSCs,倒置显微镜观察诱导后细胞形态学特征,流式细胞仪进行BMSCs表面抗原鉴定,对诱导后的细胞进行Nestin、NSE、GFAP免疫细胞化学染色鉴定。结果：培养的细胞经流式细胞仪检测,符合BMSCs表面标志特征。各对照组诱导后阳性细胞率均高于空白组,P〈0．01,其中丹参组Nestin阳性细胞率高于β-巯基乙醇组,P〈0．01,丹参组NSE阳性细胞率高于β-巯基乙醇组,P〈O．05;各诱导组GFAP表达为阴性。结论：丹参水煎液可以诱导BMSCs向神经元样细胞分化。     

骨髓基质干细胞分化为神经元样细胞迁移能力变化的研究

目的研究体外定向诱导骨髓间充质干细胞(BMSCs)分化为神经元样细胞的方法,探讨其分化后迁移能力变化的分子机制。方法体外培养BMSCs,以β-巯基乙醇(BME)1 mmol·L-1诱导分化,于诱导后12 h、24 h分别观察细胞形态变化,RT-PCR鉴定神经元特异性烯醇化酶(NSE)、神经丝蛋白(Neurofilament)、胶质纤维酸性蛋白(β-tubulinⅢ)mRNA的变化。Western blot检测CXCR4表达变化,细胞迁移实验检测BMSCs诱导前后迁移能力的变化。结果诱导后,BMSCs胞体收缩,突起伸出;RT-PCR发现诱导出的神经元样细胞的NSE、Neurofilament、β-tubulinⅢmRNA明显增加;Western blot结果表明神经元样细胞表面CXCR4的表达明显增加,细胞迁移实验发现神经元样细胞向SDF-1α的迁移能力明显增加。用CXCR4特异的抑制剂AMD3100处理后细胞迁移被明显抑制。结论在体外骨髓基质干细胞以BME为诱导剂可定向分化为神经元样细胞,且发现其迁移能力明显增加,其机制可能与其表面CXCR4表达上调有关。     

鹿茸精诱导大鼠骨髓间充质干细胞分化为神经元样细胞

目的:探讨鹿茸精体外定向诱导SD大鼠骨髓间充质干细胞分化为神经元样细胞。方法:通过贴壁法分离大鼠骨髓间充质干细胞,体外扩增培养。鹿茸精定向诱导分化为类神经元样细胞。光镜下观察细胞形态,免疫细胞化学检测神经细胞特异性抗原标志物神经元烯醇酶(NSE)、巢蛋白(Nestin)、胶质纤维酸性蛋白(GFAP)的表达。结果:大鼠骨髓间充质干细胞可通过贴壁法成功分离并可在体外大量扩增。鹿茸精诱导3小时后大部分骨髓间充质干细胞转变为神经元样细胞,出现胞体和突起,免疫细胞化学染色NSE及Nestin呈阳性,GFAP阴性。结论:鹿茸精可在体外诱导大鼠骨髓间充质干细胞分化为神经元样细胞。     

大鼠脂肪间充质干细胞的分化潜能鉴定及XIAP基因修饰*

目的分离培养扩增大鼠脂肪源间充质干细胞(ADSCs),以活体标记并鉴定其分化潜能,了解ADSCs的X连锁凋亡抑制蛋白（XIAP）基因修饰的可行性。方法无菌条件下取大鼠一侧腹股沟脂肪组织,Ⅰ型胶原酶消化法分离培养ADSCs,胰酶消化法传代扩增。检测细胞分化为脂肪细胞、软骨细胞及成骨细胞的潜能,转染XIAP表达质粒进入ADSCs,通过Western blotting等方法检测XIAP的表达能力。结果 ADSCs呈长梭形漩涡样生长,细胞流式鉴定显示CD29、CD44、CD90、CD105均呈高表达,并在特定诱导剂下分化为脂肪细胞、软骨细胞或成骨细胞。XIAP转染后显像经XIAP基因修饰的脂肪间充质干细胞在PVDF膜的相应分子质量区域出现相应的条带。结论脂肪源干细胞易于培养和传代扩增,并可活体标记,具有多向分化潜能,可作为组织工程的种子细胞。     

基因修饰的脂肪间充质干细胞的研究进展

脂肪间充质干细胞（ADSCs）是来源于脂肪组织的具有多向分化潜能的细胞群，是细胞疗法的理想来源。 基因修饰的脂肪间充质干细胞不仅具有ADSCs的全部特性，而且能够高效表达某些外源基因，加强其在疾病治疗中 的疗效，为常规的临床治疗方法难以治愈的疾病带来了新的转机。本文就近年来的相关进展进行综述，以期为基因 修饰的ADSCs在临床研究的应用上提供借鉴。     

胎盘间充质干细胞向神经细胞诱导的实验研究

目的间充质干细胞(MSCs)具有自我更新和多向分化能力的特点,尽管其主要来源骨髓间充质干细胞(BMSCs)已被认为是治疗多种疾病的良好细胞来源。但在严重感染或随着年龄的增长骨髓细胞数及增殖、分化能力均明显下降等情况下,就无法顺利获得足量可用于治疗的BMSC,有必要寻找MSC的新来源。方法消化胎盘组织、贴壁培养获得基质细胞;用流式细胞仪检测其细胞表面标志;比较叔丁对甲氧酚(butylated hydroxyanisole,BHA)、复方丹参注射液、β-巯基乙醇(BME)等对培养的基质细胞向神经细胞分化的作用;采用免疫细胞化学的方法对分化的细胞进行鉴定。结果胎盘组织中分离出的基质细胞与骨髓间充质干细胞有相似形态和细胞表面标志,并可诱导表达神经元和星型胶质细胞标志神经元特异性烯醇化酶(neuron specific enolasen,NSE)、神经微丝(neurofilament,NF)和胶质纤维酸性蛋白(glial fibrilament acidic protein,GFAP)。结论胎盘组织中存在能分化为神经元样细胞的间充质干细胞。胎盘间充质干细胞可能是一种可为临床治疗提供丰富新来源的间充质干细胞。     

ATRA、bFGF对成人骨髓间充质干细胞分化为神经元样细胞的作用

目的 :体外探讨ATRA和bFGF对成人骨髓间充质干细胞分化为神经元样细胞作用。方法 :采用Ficoll paque(1 0 77g/ml)分离液从骨髓分离出人骨髓间充质干细胞 ,体外扩增 ,以bFGF/ATRA为诱导剂 ,再加入BME、BHA、DMSO ,诱导期间观察细胞形态、数目的变化 ,并通过免疫细胞化学鉴定神经元烯醇化酶、神经丝蛋白、胶质纤维酸性蛋白的表达情况。结果 :免疫细胞化学显示在此诱导条件下 80 %的细胞表达NSE ,86 %的细胞表达NF M。结论 :ATRA和bFGF能诱导MSCs分化为神经元样细胞 ,而且具有比其他作者报道的更高的阳性转化率     

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.     

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.     

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.