双功能域重组FN多肽抑制癌细胞浸润能力的研究

在制备了两个Cell Ⅰ-Hep Ⅱ 双结构域重组FN多肽(CH50和CH56)的基础上,研究其抑制肿瘤细胞浸润能力的作用。两个多肽的结构差异是CH50中删除了Cell I和HepⅡ之间的Ⅲ-11和ED-A结构顺序。CH50(ED_(50)为30.2 nmol/L)结合细胞的能力略高于CH56(ED_(50)为45.4 nmol/L)。两种多肽均可显著抑制黑色素瘤B16/F1细胞结合层粘素的能力,抑制作用相同。在体内肿瘤浸润抑制试验中,两种多肽均可显著抑制癌细胞浸润能力,使肺转移结节数降低80％左右。结果提示:Ⅲ-11和ED-A结构顺序对Cell Ⅰ-Hep Ⅱ 双结构域多肽结合细胞的能力有一定的影响,但删除Ⅲ-11和ED-A不是重组多肽抑制肿瘤转移的决定因素,Cell I和Hep Ⅱ 这两个结构域单独连接在一起是其抑制肿瘤细胞转移的结构基础。     

NIH 3T3细胞转化前后细胞骨架及细胞表面纤维粘连蛋白的免疫荧光观察

本实验用抗纤维粘连蛋白(FN)亲和层析纯抗体和抗管蛋白抗体及鬼笔环肽,以免疫荧光组织化学方法,对NIH3T3细胞转染人肺腺癌细胞系AGZY基因组DNA前后细胞表面FN及细胞内骨架系统进行染色观察。结果表明,细胞在发生转化后,微丝及微管均表现出明显受损,细胞骨架结构不清,呈现为弥散样荧光;细胞表面FN大量减少,仅及正常NIH3T3细胞的1/9,其分布也由细丝形成的网状,变成斑点或斑块状。这一结果进一步证实,细胞恶变是涉及到细胞骨架系统及膜表面糖蛋白变化的复杂过程,并预示这些变化可能就是导致细胞形态发生变化、细胞失去正常生长调控的原因之一。     

Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling

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Polymer hydration and stiffness at biointerfaces and related cellular processes

The direct and indirect (by changing mechanical properties) effects of hydration at interfaces on cellular processes and tissue diseases are reviewed. The essential effect of substrate stiffness on cellular processes was demonstrated in the last decade. The combined effect of surface stiffness and hydration at interfaces has garnered much less attention, though hydration and dehydration play important roles in biological processes. This review focuses on the studies that demonstrate how hydration affects biological processes at interfaces. Elevated sodium and dehydration stimulate inflammatory signaling in endothelial cells and promote atherosclerosis. Various types of implant and blood contacting device coatings with varied surface stiffness and hydration have been reported. Effect of hydration on polymer modulus of elasticity and viscoelasticity was discussed taking into account cells adhesion, migration, proliferation, differentiation on surfaces with various degree of hydration. Future directions of research were considered, including the use of nanotechnology to regulate the hydration degree.     

止消通脉宁对转化生长因子-β_1诱导的人肾小管上皮细胞Ⅰ、Ⅲ型胶原及纤连蛋白mRNA表达的影响

目的探讨止消通脉宁含药血清对转化生长因子-β1（TGF-β1）诱导的人肾小管上皮细胞（HK-2）Ⅰ型胶原（ColⅠ）、Ⅲ型胶原（ColⅢ）和纤连蛋白（FN）mRNA表达的影响。方法将HK-2细胞用含10%胎牛血清的DMEM/F12（1∶1）培养基培养,分为空白对照组、TGF-β1诱导组（TGF-β110 ng/mL）、空白血清对照组（TGF-β110 ng/mL＋10%空白血清）、干预1组（TGF-β110 ng/mL＋10%低剂量止消通脉宁含药血清）、干预2组（TGF-β110 ng/mL＋10%中剂量止消通脉宁含药血清）、干预3组（TGF-β110 ng/mL＋10%高剂量止消通脉宁含药血清）。药物干预24 h后,荧光定量PCR检测ColⅠ、ColⅢ和FN的mRNA表达。结果 HK-2细胞经TGF-β1诱导后,ColⅠ、ColⅢ和FN的mRNA表达显著上升,与空白对照组比较,差异有统计学意义（P〈0.05）。经止消通脉宁含药血清干预后,其表达逐步下降,与单纯TGF-β1诱导组比较,差异有统计学意义（P〈0.05）。空白血清无此作用。结论止消通脉宁在一定程度上能够抑制TGF-β1诱导的人肾小管上皮细胞ColⅠ、ColⅢ和FN的mRNA表达,减少细胞外基质成分的分泌,具有防治肾间质纤维化作用。     

前列宁胶囊调控MMP-2影响细胞外基质对良性前列腺增生治疗的影响

目的:观察前列宁胶囊(QC)对基质金属蛋白酶-2(MMP-2)介导的细胞外基质(ECM)的影响,探讨QC对BPH的治疗机制。方法:SD大鼠随机分为空白组,BPH模型组,QC低、中、高观察组,建立BPH模型,QC干预,ELISA法检测大鼠血清MMP-2、FN、Collagen IV、LN; BPH-1细胞培养,分别加入MMP-2和未加MMP-2刺激因子,QC干预,MTT法观察细胞活性,Q-PCR及Western-Blot分别检测MMP-2、FN、Collagen IV、LN基因及蛋白表达(未加MMP-2),加入MMP-2组检测FN、Collagen IV、LN。结果:QC各剂量组大鼠血清中的FN、LN、Collagen IV含量降低,MMP-2升高(P 0. 05 or P 0. 01);BPH-1细胞培养QC干预,加入及未加入MMP-2刺激因子细胞活力均有下降,以48 h后最明显;加入MMP-2刺激因子FN、Collagen IV、LN基因及蛋白表达明显低于未加MMP-2刺激因子,差异有统计学意义。结论:QC对BPH具有治疗作用,QC调控MMP-2介导细胞外基质FN、Collagen IV、LN基因和蛋白表达可能是其治疗BPH机制之一。     

基于TGF-β1/p38MAPK/FN信号通路的放射性食管炎发病机制的研究

目的从黏膜修复角度探讨放射性食管炎的发病机制,并明确是否与TGF-β1/p38MAPKs/FN信号通路相关。方法 HE染色法对放射性食管炎标本进行病理分析,Real-time PCR法检测标本FN、TGF-β1基因表达水平,Western blot法检测组织蛋白TGF-β1、p38、FN的表达。结果 SD大鼠发生放射性食管炎后第一周体质量、进食量、进水量明显下降(P<0.05),第四周恢复;病理方面,第一、二周食管黏膜层破坏,第四周出现再生;黏膜相关细胞因子TGF-β1、FN与病理变化一致,TGF-β1、p38MAPK蛋白表达先上升后下降,而FN蛋白表达先下降后上升。结论 TGF-β1/p38MAPK/FN信号通路可能参与了其黏膜修复过程。     

Fructosamine-6-phosphates are deglycated by phosphorylation to fructosamine-3,6-bisphosphates catalyzed by fructosamine-3-kinase (FN3K) and/or fructosamine-3-kinase-related-protein (FN3KRP)

Nonenzymatic glycation of proteins and some phospholipids by glucose and other reducing sugars (a.k.a Maillard reaction) is an unavoidable result of the coexistence of these sugars and the affected macromolecules in living systems. The consequences of this process are deleterious both in the intracellular and extracellular environments as evidenced by the close association between increased nonenzymatic glycation and complications of diabetes. Because of these considerations, we have proposed that the intrinsic toxicity of glucose and other sugars is counteracted in vivo by active deglycation mechanisms including transglycation of Schiff's bases and FN3K-dependent breakdown of fructosamines. While this modified hypothesis is receiving increasing experimental support, several issues regarding glycation/deglycation remain unresolved. Two such important questions are In this paper we propose a resolution of both these quandaries by proposing that fructosamine-6-phosphates are deglycated by phosphorylation to fructosamine-3,6-bisphosphates catalyzed by FN3KRP and/or possibly FN3K. We provide some preliminary evidence in support of this hypothesis and outline experimental approaches for definitive tests of this hypothesis. The potential medical implications of this finding are not clear yet but, if correct, this observation is likely to have a major impact on our understanding of the very basic and hitherto unexplored aspect of glucose metabolism and chemistry in vivo. One can imagine that, at some point in the future, measurement of FN3K/FN3KRP activity may be of diagnostic value in assessing an individual's susceptibility to diabetic complications. Further down the road, one can also envision a gene therapeutic intervention to bolster FN3K/FN3KRP-based antiglycation defenses.     

Nanofiber technology in the ex vivo expansion of cord blood-derived hematopoietic stem cells

Umbilical cord blood (CB) can be used as an alternative source of hematopoietic stem cells (HSCs) for transplantation in hematological and non-hematological disorders. Despite several recognized advantages the limited cell number in CB one unit still restricts its clinical use. The success of transplantation greatly depends on the levels of total nucleated cell and CD34+ cell counts. Thus, many ex vivo strategies have been developed within the last decade in order to solve this obstacle, with more or less success, mainly determined by the degree of difficulty related with maintaining HSCs self-renewal and stemness properties after long-term expansion. Different research groups have developed very promising and diverse CB-derived HSC expansion strategies using nanofiber scaffolds. Here we review the state-of-the-art of nanofiber technology-based CB-derived HSC expansion.