穿心莲内酯促进骨折骨愈合作用机制的研究进展

骨折后的愈合状态直接影响患者的生活质量,如何提高骨折患者骨愈合效果是亟待解决的问题。穿心莲内酯是穿心莲中主要活性成分,可能通过促进成骨细胞增殖,抑制核因子κB（NF-κB）信号通路激活,激活Wnt/β-连环蛋白（Wnt/β-catenin）信号通路,调节护骨素/细胞核因子κB受体活化因子配基（OPG/RANKL）信号通路,调节成骨基因表达产物,改善软骨细胞功能,抑制雌激素相关受体α（ERRα）信号通路等多途径促使骨愈合。总结了穿心莲内酯促进骨折骨愈合作用及其作用机制,希望为穿心莲内酯的临床使用提供依据。     

NF-κB活化在急性胰腺炎发病机制中的作用

急性胰腺炎(AP)发病机制复杂,其相关的信号分子和信号通路尚不明确,目前仍是研究的热点.AP信号通路的共同途径是核因子NF-κB活化.NF-κB是一种核转录因子,调控多种炎症因子的基因转录,与机体免疫、炎症等过程密切相关.从胰腺及胰外脏器(肺、肝、单核巨噬细胞和内皮细胞)中NF-κB活化阐述了NF-κB活化在AP发病机制中的作用,以便于提高对AP的治疗水平.     

TLR/MyD 88/NF-κB信号通路参与不同疾病作用机制研究进展

TLR/MyD88/NF-κB信号通路是机体炎症体系中的重要途径,其广泛存在于各种组织细胞中,参与多种疾病的发生与调控,如自身免疫性疾病、炎症性疾病、感染性疾病、过敏性疾病等。Toll样受体(TLR)是一种跨膜蛋白,能够识别多种类型的病原相关分子模式(如脂多糖、尿酸钠晶体、病毒双链RNA等),引起机体炎症免疫应答,而所有的TLR都能激活MyD88依赖性途径,从而活化NF-κB,最终导致炎症介质和细胞因子的释放,起到抗炎免疫调节作用。目前,对TLR/MyD88/NF-κB信号通路的研究较为深入,同时也取得了一定的进展。该文将从TLR/MyD88/NF-κB信号通路在机体中的作用机制入手,对其在不同疾病中的调控作用进行综述。     

穿心莲内酯对人肺腺癌A549细胞NF-κB通路的调控作用

目的探讨穿心莲内酯对肿瘤细胞生长的作用及机制。方法人肺腺癌A549细胞分别与穿心莲内酯1.5～30μmol·L-1作用24h,以及穿心莲内酯30μmol·L-1作用4～24h。用MTT法检测A549细胞存活率;Western印迹法检测在肿瘤坏死因子α(TNF-α)10μg·L-1刺激下,穿心莲内酯30μmol·L-1对NF-κB信号通路中的相关蛋白NF-κB抑制因子α(IκBα)、磷酸化IκBα、IκB激酶β(IKKβ)和磷酸化IKKβ表达的影响;ELISA法检测穿心莲内酯对A549细胞核内NF-κBDNA结合活性的影响。结果穿心莲内酯的浓度和作用时间与A549细胞的存活率密切相关,穿心莲内酯30μmo·lL-1作用24h,A549细胞的存活率下降到(22.0±1.2)%,而穿心莲内酯1.5μmol·L-1作用24h或者穿心莲内酯30μmol·L-1作用4h对A549细胞的存活率几乎无影响。Western印迹法显示,穿心莲内酯能够抑制TNF-α诱导的NF-κB信号通路中IKKβ的磷酸化,抑制IκBα的磷酸化,推迟IκBα的降解,对IKKβ的表达无影响。穿心莲内酯还能够抑制TNF-α诱导的A549细胞核内NF-κBp65蛋白的DNA结合活性,抑制率达32%。结论穿心莲内酯通过影响NF-κB信号通路抑制A549细胞的生长。     

一氧化氮供体型非甾体抗炎药抗肿瘤作用机制研究现状

概述一氧化氮供体型非甾体抗炎药（NO—NSAIDs）抗肿瘤药理学实验研究，着重综述该类药物抗肿瘤作用机制研究进展。在NO-NSAIDs中，NO-阿司匹林被研究得最为深入，其有多种作用机制，包括阻断Wnt信号通路、抑制NF-κB的激活、抑制一氧化氮合酶、调控环氧合酶-2、调节Keapl-Nrf2和MAPK信号通路等，这些机制可能在该类药物的抗癌作用中扮演着不同角色。     

类风湿关节炎中NF-κB信号通路相关微小RNA的研究进展

微小RNA（miRNA）是一类短链非编码RNA分子,主要参与癌症、病毒感染、炎症、自身免疫病等的生理和病理过程。核因子κB（NF-κB）是一个基因调节功能广泛的转录因子,参与炎症、细胞增殖、肿瘤发育、学习、记忆等不同的生物过程。一些研究提示miRNA与NF-κB通路关系密切,在调控NF-κB通路中起着抑制或激活作用。本文就类风湿关节炎中参与NF-κB信号调节的miRNA及其作用机制的研究进展作一综述。     

Dvl交叉调控Wnt及NF-κB信号通路在类风湿性关节炎骨侵蚀中的作用研究进展

Wnt信号通路在骨细胞的成熟、分化和凋亡过程中具有重要的调控作用,通过调控成骨细胞和破骨细胞从而达到骨代谢的动态平衡。Wnt通路激活不足或过度激活均参与了类风湿性关节炎的发生和发展。核因子κB(NF-κB)是一种具有多向性调节作用的转录因子,参与细胞的生长、发育、凋亡等多种生理功能。如果NF-κB通路被不适当的活化,则可导致多种自身免疫和炎症性疾病,这其中就包括类风湿性关节炎。Dvl蛋白是Wnt信号通路中关键蛋白,有研究发现其也参与NF-κB通路的调控。因此,通过对Dvl蛋白交叉调控Wnt和NF-κB通路的研究,有可能为我们提供治疗类风湿关节炎新的药物靶点。     

中药单体成分及复方促进骨折愈合的作用机制研究进展

中药在治疗骨折愈合过程中具有多成分、多途径、多靶点的作用特点,对于具有复杂病理机制的骨折具有较好的治疗优势和潜力。笔者对中药单体成分及复方促进骨折愈合的作用机制进行了归纳,发现内脂素A、葛根素等可通过激活丝裂原活化蛋白激酶（MAPK）信号通路,续骨丹、固本增骨方等可通过激活骨形态发生蛋白（BMP）信号通路,黄芩苷、牛膝多糖等可通过激活Wnt/β-catenin信号通路,芹菜素、三七皂苷等可通过激活核因子κB(NF-κB)受体激活蛋白/NF-κB受体激活蛋白配体/护骨因子（RANK/RANKL/OPG）信号通路,活血接骨复方胶囊、健骨颗粒等可通过抑制磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/AKT)信号通路,淫羊藿苷等可通过激活Notch信号通路,桃红四物汤、藏红花素等可通过激活Hippo信号通路,酸枣仁皂苷A、蛇床子素等可通过抑制NF-κB信号通路,发挥促进骨折愈合的作用。     

Swiprosin-1/EFhd2调控免疫炎症反应的研究进展

Swiprosin-1(也称为EFhd2)是最早在T淋巴细胞中发现的一种衔接蛋白。研究发现,其在巨噬细胞、B淋巴细胞、肥大细胞等其它多种免疫细胞上也表达,并且影响免疫细胞的激活、迁移、凋亡及炎症反应,参与NF-κB、JAK-STAT、MAPK和钙信号等信号通路。该文简要综述了近年来报道的EFhd2在免疫炎症反应调节中的作用和机制,为进一步明确EFhd2作为新的免疫调控潜在靶点提供理论依据。     

丹皮酚通过抑制NF-κB信号通路诱导Tca8113细胞凋亡

目的 研究丹皮酚对核因子κB（NF-κB）信号通路的影响,探讨其诱导肿瘤细胞凋亡的分子机制。方法 将丹皮酚以不同浓度及不同时间作用于人舌鳞癌Tca8113细胞,应用MTT法观察不同浓度丹皮酚在不同作用时间下对Tca8113细胞增殖的抑制作用,Hoechst 33342荧光染色及流式细胞仪检测细胞凋亡情况,Western blot法检测凋亡相关蛋白Bax和Bcl-2,以及NF-κB信号通路组分中IκBα和p-IκBα的表达情况,并采用凝胶电泳迁移率检测（EMSA）对NF-κB活性进行测定。结果 经丹皮酚作用后,Tca8113细胞生长受到明显抑制,并呈明显的时间、剂量依赖效应关系。丹皮酚有明显诱导Tca8113细胞凋亡的作用,Western Blot 以及EMSA检测结果显示,丹皮酚上调Tca8113细胞中Bax与IκBα的表达,下调Bcl-2的表达,并能下调IκBα磷酸化及NF κB活性。结论 丹皮酚能够抑制NF-κB信号转导通路,进而抑制Tca8113细胞的增殖并诱导其凋亡。     

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.     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.     

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.     

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.