脂肪干细胞外泌体对人牙髓干细胞增殖与成骨分化的影响北大核心CSCD

目的观察人脂肪间充质干细胞来源外泌体对人牙髓干细胞增殖与成骨分化的影响。方法制备人脂肪来源的间充质干细胞和外泌体。将人牙髓干细胞随机分为3组,正常组进行常规培养,对照组进行成骨诱导分化,实验组在成骨诱导分化时添加5μg·mL^(-1)外泌体。用CCK-8法检测细胞增殖活性,用酶联免疫吸附实验法检测碱性磷酸酶活性,用Western blot法检测骨钙素和骨桥蛋白的表达情况。结果实验组、对照组和正常组的细胞相对增殖活性(光密度值)分别为0.54±0.02,0.34±0.01和0.32±0.01,碱性磷酸酶相对活性(光密度值)分别为10.37±1.26,4.89±0.94和0.71±0.03,骨钙素蛋白相对表达量分别为0.59±0.10,0.23±0.05和0,骨桥蛋白相对表达量分别为0.63±0.12,0.61±0.04和0,实验组的上述指标与对照组和正常组比较,差异均有统计学意义(均P<0.05)。结论人脂肪间充质干细胞来源的外泌体可促进人牙髓干细胞的增殖和成骨分化。     

大鼠骨髓间充质干细胞的分离增殖及分化潜能活性

目的：建立大鼠骨髓间充质干细胞（MSC）体外分离、纯化、增殖的方法，并观察其体外分化为成骨细胞及软骨细胞的潜能活性。方法：取SD大鼠的股骨及胫骨，冲取骨髓液，采用贴壁培养法分离纯化MSC，增殖，并测定其生长曲线。对第三代大鼠MSC进行成骨矿化诱导，测定其碱性磷酸酶（ALP）活性及成骨矿化情况。对第三代大鼠MSC进行诱软骨细胞的诱导分化，测定诱导后的细胞表型情况。结果：大鼠MSC为均一的梭形的成纤维细胞样生长，贴壁及增殖能力强。生长曲线呈S型。在成骨诱导剂作用下，MSC具有成骨能力，诱导后AIP活性显著提高。并出现矿化结节沉积。在成软骨诱导剂作用下，可见细胞由成纤维细胞样的梭形变为椭圆形及肾形，并分泌异染基质，甲苯胺蓝染色呈阳性，表现为软骨细胞分化特点。结论：获得的SD大鼠MSC生长旺盛，增殖能力强。在特定诱导条件下。大鼠MSC体外可定向分化为成骨细胞及软骨细胞。具有成骨及成软骨分化潜能。     

咯利普兰在骨髓间充质干细胞向成骨细胞分化中的作用

目的 研究咯利普兰在体外骨髓间充质干细胞向成骨细胞诱导分化过程中的作用.方法 体外分离培养小鼠股骨骨髓间充质干细胞,随机分为咯利普兰10 μmol/L组(A组)和对照组(B组).骨髓间充质干细胞向成骨诱导分化后,检测碱性磷酸酶(ALP)活性;Western blot检测Runx2和骨钙素表达;茜素红染色观察钙结节形成情况.结果 与B组相比,A组ALP活性及Runx2、骨钙素表达均增加(P＜0.01或P＜0.05),钙结节形成更加明显.结论 咯利普兰能提高体外骨髓间充质干细胞向成骨细胞诱导分化的能力.     

大鼠骨髓间充质干细胞的体外分离与培养

目的 建立体外分离纯化及培养扩增大鼠骨髓间充质干细胞的方法.方法 应用全骨髓贴壁培养法分离培养大鼠骨髓间充质干细胞,并进行细胞传代培养.倒置显微镜下观察细胞形态及生长特征,测定细胞生长曲线,通过流式细胞仪检测细胞表面标志物,取第3代细胞分别加入成骨、成脂诱导剂并采用碱性磷酸酶染色及Von Kossa染色鉴定成骨能力,以油红O染色鉴定成脂能力.结果 获取的大鼠骨髓间充质干细胞形态呈均一成纤维细胞样,并呈集落样生长.传至第3代细胞纯度可达97%以上,其细胞表型CD29、CD44、CD105、CD166呈阳性表达,CD34、CD80、CD86呈阴性表达.经成骨诱导后细胞碱性磷酸酶染色及Von Kossa染色呈阳性,成脂诱导后细胞油红O染色呈现阳性.结论 应用全骨髓贴壁法可以分离培养出高纯度的大鼠bMSCs,培养的细胞扩增迅速、生物学特性稳定,是一种较为理想的体外分离扩增bMSCs的培养体系.     

诱导兔骨髓间充质干细胞定向分化为成骨细胞和软骨细胞的研究

目的：探讨兔骨髓间充质干细胞(MSC)体外分离培养、增殖，以及向成骨细胞和软骨细胞定向诱导分化的条件，为骨、软骨缺损的修复和重建提供种子细胞。方法：抽取兔髂骨及胫骨的骨髓液，经密度梯度离心法及塑料板贴壁培养法分离纯化出MSC，并增殖。对第二代MSC进行成骨矿化诱导，测定其碱性磷酸酶(ALP)活性及成骨矿化情况。并对第二代MSC进行诱软骨特定培养液诱导，对诱导细胞进行甲苯胺蓝染色，测定诱导后的软骨细胞表型。结果：MSC为梭型的成纤维细胞样贴壁生长，增殖能力强。在成骨诱导剂作用下，MSC具有成骨能力，诱导后ALP活性明显提高，并且出现矿化结节沉积。在成软骨诱导剂作用下，可见细胞由成纤维样的梭形变为椭圆形及肾形，并分泌基质，甲苯胺蓝染色呈阳性，表现为软骨细胞分化特点。结论：在特定诱导条件下，兔骨髓MSC体外可定向诱导分化为成骨细胞和软骨细胞，可用于组织工程骨和软骨组织的修复和重建。     

母体来源人胎盘间充质细胞的分离培养及其分化能力的研究

目的探讨胎盘母体来源间充质细胞的分离、培养方法及其向脂肪和成骨诱导分化潜能。方法采用酶消化获得母体来源胎盘间充质干细胞体外扩增后,利用流式细胞仪检测其表面标志物;进行诱导分化后,采用油红O及茜素红染色鉴定其向脂肪和成骨诱导分化潜能。结果体外培养的母体来源胎盘间充质干细胞呈长梭形,细胞形态均一;细胞表面标志鉴定：CD73、CD90和CD105呈阳性表达,而CD14、CD34、CD45,和HLA—DR呈阴性表达;细胞诱导分化后,经油红O、茜素红染色证实其可分化为脂肪细胞和成骨细胞。结论建立了母体来源胎盘间充质干细胞的分离培养方法;证实其具有成脂、成骨分化潜能,有望成为细胞治疗及组织工程更为理想的种子细胞。     

美洲大蠊提取物对大鼠骨髓间充质干细胞的成骨分化诱导作用

目的 测定4种美洲大蠊提取物对大鼠骨髓间充质干细胞(bMSCs)的成骨分化诱导作用。方法 用4种提取物分别对bMSCs进行诱导培养。14 d后,用qPCR测定I型胶原α1和碱性磷酸酶的基因转录水平,比色法测定碱性磷酸酶的活性,免疫细胞化学法检测骨钙素、骨桥蛋白的水平。21 d后,用茜素红染色观察钙化结节的形成情况。结果 与对照组比较,4种美洲大蠊提取物各处理组检测出的成骨分化指标均有不同程度升高,某些浓度下差异显著。其中,XD02的诱导效果最好,且细胞毒性最小。结论 4种美洲大蠊提取物均具诱导骨髓间充质干细胞成骨分化的作用。美洲大蠊提取物有望成为干预骨质疏松的营养添加剂或药物。     

大黄素对体外大鼠骨髓基质细胞向成骨细胞方向分化的影响

目的 :观察大黄素对骨髓基质细胞向成骨细胞方向分化的影响 ,探讨大黄素对干细胞分化方向的调节作用。方法 :用密度梯度离心的方法和传代贴壁筛选的方法相结合 ,分离纯化骨髓基质细胞。对硝基苯磷酸盐法判断是否成功诱导骨髓基质细胞向成骨细胞方向分化 ,碱性磷酸酶染色法、放射免疫测定法观察大黄素对骨髓基质细胞向成骨细胞方向分化的影响。结果 :结合密度梯度离心的方法和传代贴壁筛选的方法 ,分离纯化后可得到成分较为均一的骨髓基质细胞 ,其间存在有间质干细胞 ,经诱导后向成骨细胞方向分化。大黄素可增加大鼠骨髓基质细胞成骨诱导后细胞碱性磷酸酶的含量 ,其中10 -6mol·L-1浓度组作用 7d时效果明显。大黄素在 2 .5× 10 -7～ 10 -5mol·L-1浓度范围内未能增加细胞上清液和细胞裂解液中骨钙素含量。结论 :大黄素能促进骨髓基质细胞向成骨细胞方向分化 ,这一作用主要体现在骨形成过程的早期 ,对矿化期没有促进作用。     

山柰酚体外促成骨分化作用研究

目的 探究不同浓度的山柰酚对骨髓间充质干细胞增殖及成骨分化的影响。方法 使用含不同浓度山柰酚的培养基培养骨髓间充质干细胞,通过CCK8检测细胞增殖情况,碱性磷酸酶活力检测细胞的碱性磷酸酶表达水平,茜素红染色观察钙化结节形成情况,实时荧光定量聚合酶链式反应检测细胞Runx2、OCN成骨相关基因的表达水平。结果 10^-4mol/L山柰酚对骨髓间充质干细胞增殖分化有明显抑制作用(P <0.05),10^-5、10^-8mol/L山柰酚对骨髓间充质干细胞增殖分化无影响(P> 0.05),10^-6、10^-7mol/L山柰酚对骨髓间充质干细胞增殖有明显促进作用(P <0.05),其中10^-6mol/L山柰酚还可促进骨髓间充质干细胞的碱性磷酸酶表达、成骨矿化以及Runx2、OCN成骨相关基因的表达。结论 10^-6mol/L山柰酚可以促进骨髓间充质干细胞增殖及成骨分化。     

雷洛昔芬通过促进一氧化氮释放诱导脂肪干细胞向成骨细胞分化

目的探讨雷洛昔芬诱导脂肪干细胞向成骨细胞分化作用及其机制。方法从大鼠体内提取分离脂肪干细胞,并进行多向分化能力鉴定。在成骨诱导培养液中加入不同浓度雷洛昔芬(0、0.01、0.1、1μmol.L-1)、非选择性一氧化氮合成酶抑制剂L-硝基精氨酸甲酯(L-NAME(1 mmol.L-1))、雷洛昔芬(1μmol.L-1)+L-NAME(1 mmol.L-1),在共同条件培养14～28 d,测定各项成骨细胞形成指标。结果雷洛昔芬(0.01～1μmol.L-1)能明显提高脂肪干细胞胞质一氧化氮的释放和成骨细胞分化标志基因(碱性磷酸酶、骨形态发生蛋白2和Ⅰ型胶原)的表达以及矿化结节的生成,L-NAME可以拮抗雷洛昔芬引起的胞质一氧化氮的释放,并同时抑制雷洛昔芬诱导脂肪干细胞向成骨分化的作用。结论雷洛昔芬可以促进胞质一氧化氮释放,从而诱导脂肪干细胞向成骨细胞分化。     

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.