人骨髓来源间充质干细胞的体外分离方法及鉴定

目的探讨人骨髓来源间充质干细胞的体外分离方法及鉴定。方法密度梯度离心从人骨髓分离单个核细胞,接种培养3h后频繁换液,培养至第14d时用0.25%胰酶室温作用2min移种后继续培养至第21d。采用流式细胞术检测收获细胞的表型分子。收获细胞在特定条件下诱导培养至第14d,分别采用茜素红染色、甲苯胺蓝染色和油红染色进行鉴定。结果第21d时均一的长梭状成纤维样细胞铺满瓶底,它们高表达CD105、CD73、CD90并低表达CD45、CD34和CD14,能够被诱导分化为骨细胞、软骨细胞和脂肪细胞。结论密度梯度离心法结合贴壁筛选可以成功地从人骨髓分离获得间充质干细胞,接种初期频繁换液体及后期控制胰酶作用时间可以有效减少造血系细胞混杂。     

两种不同方法分离、培养大鼠骨髓基质干细胞的比较研究

目的 对分别采用密度梯度离心法和贴壁筛选法分离、培养的大鼠骨髓基质干细胞（MSCs）的形态学和增殖动力学进行初步研究,以逐步完善MSCs体外培养体系.方法 取1月龄SD大白鼠胫骨和股骨骨髓,分别采用密度梯度离心法和贴壁筛选法进行体外分离、培养.倒置显微镜下进行MSCs的形态学观察和记录,MTT法测定细胞增殖度,绘制各自培养体系的传一代细胞生长曲线并比较.结果 培养获得的MSCs呈梭形或多角形,表面有不规则突起.采用密度梯度离心法培养获得的细胞纯度高,生长速率较贴壁筛选法获得的细胞快,增殖显著.另外,用小牛血清培养的MSCs生长曲线与文献报道的用胎牛血清培养的MSCs生长曲线一致。结论 密度梯度离心法可认为是目前体外培养MSCs的理想方法.用于体外培养MSCs的血清可能有更多选择。     

大鼠骨髓间充质干细胞的培养、扩增与鉴定

目的:建立大鼠骨髓间充质干细胞(MSCs)分离及培养的方法,探讨体外培养MSCs的生物学特性.方法:采用密度梯度离心法和贴壁筛选法纯化MSCs,镜下连续观察细胞的形态变化.流式细胞仪鉴定其表面抗原CD29、CD34、CD44和CD45的表达情况.结果:原代MSCs呈集落状生长,细胞呈梭形、纺锤形,呈放射状排列.传代后大都均匀分布生长,细胞生长迅速,倍增时间约45.5 h.流式细胞术鉴定表明,培养的第3代和第5代MSCs CD44、CD29阳性,CD45和CD34阴性.结论:采用密度梯度离心法结合贴壁筛选法可成功分离和培养大鼠的骨髓MSCs,MSCs可以作为组织工程中种子细胞的来源.     

两种猪自体骨髓间充质干细胞培养方法的比较

目的比较猪应用单纯直接贴壁法和密度梯度离心结合直接贴壁法两种方法分离、纯化、扩增骨髓间充质干细胞(MSCs)的培养效率,为临床应用提供理论依据和实验方法。方法取滇南小型猪的骨髓液用单纯直接贴壁法和密度梯度离心结合贴壁培养法两种方法分离猪骨髓间充质干细胞,体外培养扩增,绘制其生长曲线,通过显微镜观察培养细胞的生物学形状。结果直接贴壁法收集到的细胞扩增速度较慢,密度梯度离心法收集到的细胞扩增速度较快,细胞培养后成梭形。结论密度梯度离心结合贴壁培养法较单纯的直接贴壁法培养骨髓间充质干细胞的培养效率更高。体外培养的猪骨髓间充质干细胞生长稳定,增殖力较强。     

大鼠脑星形胶质细胞的体外培养及鉴定

目的 探讨新生大鼠大脑皮质星形胶质细胞的分离、培养以及鉴定方法.方法 取出生1～2 d的Wistar大鼠大脑皮质,用机械法和胰酶消化法分散细胞,制成细胞悬液,差速黏附处理后,将未贴附的细胞接种培养.待细胞铺满瓶底后,置摇床摇晃,舍弃含脱落细胞的培养液,细胞传代.GFAP免疫细胞化学染色鉴定.结果 成功分离培养了原代星形胶质细胞,传代培养的星形细胞形态典型,纯度可达95%以上.结论 成功建立了大鼠星形胶质细胞体外培养方法.     

人骨髓间充质干细胞体外分离培养方法的比较研究

目的 比较Ficoll密度梯度离心法分离人骨髓间充质干细胞(mesenchymal stem cells,MSCs)与全骨髓培养法之间的差异,以期建立一种简便、实用的基于临床移植需要的MSCs分离方法.方法 分别应用上述两种方法分离MSCs,比较用两种方法的细胞形态、MSCs细胞得率及以及细胞表面标志的差异.结果 两种方法均能有效培养出骨髓MSCs,且获得的第二代MSCs细胞形态无明显差异,细胞形态均一,为长梭形或三角形.5 ml骨髓细胞分离培养后,Ficoll密度梯度离心法获得的MSCs细胞总数显著小于全骨髓培养法(t=.639,P＜0.01).Ficoll密度梯度离心法与全骨髓培养法获得的第二代MSC8 CD29、CD105、CD105、CD34阳性表达率的差异无统计学意义(t分别为0.809、0.659、0.277、0.191,P均＞0.05),但前者的HLA-DR阳性表达率明显低于后者,差异具有统计学意义(t=2.347,P＜0.05).结论 与Ficoll密度梯度离心法相比较,全骨髓培养法分离MSCs具有培养时间较短,细胞得率较多的优点,虽纯度相对较低,但仍是一种较好的MSCs分离方法.     

MSCs分离培养及定向分化为血管内皮细胞的研究

目的建立分离和培养大鼠骨髓源间充质干细胞（MSCs）的方法及定向分化为血管内皮细胞诱导条件的优化。方法淋巴细胞分离液（比重1．077g／m1）密度梯度离心法分离单个核细胞（MNC），在含10％胎牛血清L—DMEM培养基中培养，并传代扩增MSCs；选取状态较稳定的第4代细胞，分别用含10％胎牛血清和2％胎牛血清的诱导液（终浓度为10ng／mlVEGF、2ng／mlbFGF的DMEM培养液）继续培养，于第7、14天用流式细胞术分析CD34的表达情况，免疫组化法观察FVⅢ的表达情况。结果密度梯度离心结合贴壁培养法能有效分离纯化MSCs，细胞呈均一的成纤维细胞样，流式细胞术分析MSCs结果显示，CD34阳性率为1．01％、CD29阳性率为97．32％；诱导14d后免疫组织化学法检测FVⅢ的表达，10％和2％胎牛血清诱导体系细胞的阳性率分别为12．21％和91．43％。结论密度梯度离心结合贴壁培养法能有效分离纯化MSCs；就诱导效果而言，2％胎牛血清诱导体系明显好于10％胎牛血清诱导体系，说明低浓度的胎牛血清更有利于MSCs向血管内皮细胞分化。     

兔骨髓间充质干细胞的分离、培养、鉴定及DiI荧光标记

目的:探讨兔骨髓间充质干细胞(MSCs)体外分离培养、表型鉴定和标记的方法.方法:采用密度梯度离心法及贴壁分离筛选法分离培养MSCs;采用免疫细胞化学方法检测细胞表面标志抗原CD29和CD106的表达,进行表型鉴定;DiI标记第3代MSCs,观察标记效率.结果:体外培养的原代MSCs 48 h内可见少量贴壁细胞,7～8 d达到90%汇合;免疫细胞化学方法检测细胞表面标志抗原CD29,CD106为阳性;DiI进行细胞标记后,荧光显微镜下见所有MSCs均被标记为红色荧光,敏感性好,标记效率高.结论:此培养方法可以作为培养兔MSCs的常规方法,为构建组织工程尿道提供充足的种子细胞.     

应用密度梯度离心法分离扩增兔骨髓基质细胞的体会

目的探讨密度梯度离心法分离培养兔骨髓基质干细胞(BMSc)的条件，为组织工程学选择合适的种子细胞奠定基础。方法采用密度梯度离心法将兔BMSc自小量骨髓中分离并培养，观察其增殖和生长特性，绘制生长曲线，测定分裂指数和贴壁率。结果兔．BMSc在第7代前性状稳定，生长曲线相似；第4天分裂指数最高为15％；传代后10h贴壁率高达90％。结论密度梯度离心法是分离兔BMSc的理想方法，BMSc能为未来组织工程提供足量种子细胞。     

大鼠坐骨神经雪旺细胞体外培养纯化的实验研究

目的:探索大鼠坐骨神经雪旺细胞体外培养纯化的方法,以获取大量的雪旺细胞应用于周围神经组织工程研究.方法:取预变性坐骨神经,去神经外膜,剪碎块后,用胰酶及胶原酶组成的混合酶消化15 min,加入含10%胎牛血清的DMEM吹打成悬液进行培养.24 h后将培养液全部吸出,组织块中的细胞游出铺满皿底后,将组织块移入新的培养皿中,反复3次后将得到雪旺细胞扩大培养,加入b-FGF(20 ng/mL),待细胞铺满瓶底的80%～90%时,即可传代.纯化后细胞行S-100免疫细胞化学鉴定.结果:双酶消化法结合差速贴壁法可去除较多杂细胞,应用b-FGF刺激雪旺细胞增殖,可获得大量高纯度的雪旺细胞,经S-100蛋白免疫细胞化学鉴定,雪旺细胞纯度达96%以上.结论:双酶消化法、差速贴壁法结合b-FGF刺激增殖的方法可从坐骨神经中分离纯化大量雪旺细胞.     

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.     

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.     

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.     

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.     

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.