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41.
壳聚糖/聚乙二醇琥珀酸酯薄膜的制备及其与肌成纤维细胞的相容性 总被引:1,自引:0,他引:1
目的:制备防粘连壳聚糖/聚乙二醇琥珀酸酯薄膜并观察其与肌成纤维细胞的相容性。方法:实验于2006-05/11在南方医科大学附属珠江医院中心实验室完成。实验材料:在透析后的壳聚糖与聚乙二醇琥珀酸酯或聚乙二醇共混后置入冻干机冻干制得壳聚糖/聚乙二醇琥珀酸酯薄膜或壳聚糖/聚乙二醇膜,并将新生2~5d的SD大鼠骨骼肌成纤维细胞种植于膜片上。实验评估:①MTT法测定肌成纤维细胞接种在不同膜片上的吸光度值,计算相对贴附率。相对贴附率=不同膜的A490nm/培养板的A490nm×100%。②MTT法测定肌成纤维细胞在不同膜片上的生长1,5d后的吸光度值。③相差显微镜下观察肌成纤维细胞的生长形貌。结果:①肌成纤维细胞在不同膜片上的贴附率:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上能良好黏附、增殖,而在壳聚糖/聚乙二醇膜、壳聚糖膜上黏附性差。联合培养12h,5d后MTT法结果显示,壳聚糖/聚乙二醇琥珀酸酯组的A值分别为0.074±0.009,0.141±0.031,分别为壳聚糖组的6.17倍和6.13倍(P〈0.05)。②肌成纤维细胞的生长特性:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯膜上的活性最高,增殖能力最强,增长速度最快,其次为壳聚糖/聚乙二醇膜,但两者差异无显著性意义(P〉0.05),而细胞在壳聚糖膜上的增殖能力较低,膜上细胞数目较少,与其他组比较差异有显著性意义(P〈0.05)。③肌成纤维细胞与不同膜片联合培养1,5d时的生长形貌:壳聚糖膜上细胞未贴壁生长,为透明的圆球形,呈游离状态,未能很好舒展,且有些皱缩,生长活力也不旺盛;细胞与壳聚糖/聚乙二醇膜、壳聚糖/聚乙二醇琥珀酸酯膜片联合培养的生长情况要明显好于壳聚糖膜,细胞相互融合成片,多呈长梭形,细胞间隙狭窄,紧密排列成束,成指纹状结构且聚集生长的趋势也更明显。结论:将接支琥珀酰基的聚乙二醇与壳聚糖共混组成的网状系统改进了膜片的力学性能,提高了膜片的柔韧性,使其成膜性更好;壳聚糖/聚乙二醇琥珀酸酯薄膜具有良好的生物相容性,肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上的黏附及生长情况明显好于壳聚糖薄膜。 相似文献
42.
43.
Bullinger KL Nardelli P Pinter MJ Alvarez FJ Cope TC 《Journal of neurophysiology》2011,106(5):2471-2485
Regeneration of a cut muscle nerve fails to restore the stretch reflex, and the companion paper to this article [Alvarez FJ, Titus-Mitchell HE, Bullinger KL, Kraszpulski M, Nardelli P, Cope TC. J Neurophysiol (August 10, 2011). doi:10.1152/jn.01095.2010] suggests an important central contribution from substantial and persistent disassembly of synapses between regenerated primary afferents and motoneurons. In the present study we tested for physiological correlates of synaptic disruption. Anesthetized adult rats were studied 6 mo or more after a muscle nerve was severed and surgically rejoined. We recorded action potentials (spikes) from individual muscle afferents classified as IA like (*IA) by several criteria and tested for their capacity to produce excitatory postsynaptic potentials (EPSPs) in homonymous motoneurons, using spike-triggered averaging (STA). Nearly every paired recording from a *IA afferent and homonymous motoneuron (93%) produced a STA EPSP in normal rats, but that percentage was only 17% in rats with regenerated nerves. In addition, the number of motoneurons that produced aggregate excitatory stretch synaptic potentials (eSSPs) in response to stretch of the reinnervated muscle was reduced from 100% normally to 60% after nerve regeneration. The decline in functional connectivity was not attributable to synaptic depression, which returned to its normally low level after regeneration. From these findings and those in the companion paper, we put forward a model in which synaptic excitation of motoneurons by muscle stretch is reduced not only by misguided axon regeneration that reconnects afferents to the wrong receptor type but also by retraction of synapses with motoneurons by spindle afferents that successfully reconnect with spindle receptors in the periphery. 相似文献
44.
Tecchio C Nadali G Scapini P Bonetto C Visco C Tamassia N Vassilakopoulos TP Pangalis GA Calzetti F Nardelli B Roschke V Gottardi M Zampieri F Gherlinzoni F Facchetti F Pizzolo G Cassatella MA 《British journal of haematology》2007,137(6):553-559
B-lymphocyte stimulator (BLyS) acts as survival factor for B lymphocytes. As Hodgkin and Reed-Sternberg (HRS) cells express receptors through which BLyS promotes their growth and chemotherapy resistance, we investgated whether this molecule was increased in sera from patients with classical Hodgkin lymphoma (cHL) and whether it correlates with clinical-pathological features and outcomes. Enzyme-linked immunosorbent assay was used to measure soluble BLyS (sBLyS) in sera from 87 patients and 33 donors; higher levels were detected in patients (mean +/- standard error 4493.9 +/- 264.9 pg/ml vs. 2687.0 +/- 200.9 pg/ml; P < 0.0001). Levels above the median value (4242.0 pg/ml) were associated with age > or = 45 years (P = 0.042), advanced stages of disease (P = 0.005), systemic symptoms (P = 0.014) and extranodal involvement (P = 0.009). Five-year failure-free survival (FFS) of patients with sBLyS below or equal to median levels was 88.6% as compared to 65.1% of those with levels above the median (P = 0.009). Statistical analyses confirmed the prognostic significance of sBLyS (P = 0.046). When patients were analysed according to variables associated with high levels, sBLyS showed an independent predictive power in terms of FFS. Our findings support the involvement of BLyS in cHL pathogenesis. The association between high serum levels and an inferior FFS indicates that sBLyS is a possible prognostic predictor with a potential significance as a therapeutic target. 相似文献
45.
46.
角质细胞与成纤维细胞混合移植修复裸鼠全层皮肤缺损的初步报告 总被引:4,自引:0,他引:4
目的:利用组织工程原理探讨修复全层皮肤缺损的理想方式。方法:以裸鼠为动物模型,在皮肤全层缺损区域分别移植纤维蛋白胶(n=10),纤维蛋白胶角质细胞悬液(n=10),纤维蛋白胶成纤维细胞悬液(n=10)以及纤维蛋白胶角质细胞成纤维细胞悬液(n=10),术后每天对伤口进行大体观察,第5,7,10,14,21,35d,分别取材活检行组织学及免疫组织化学检查。结果:移植有角质细胞组(2和4组)的创面愈合快,术后10d组织学提示创面完全上皮化,抗人特异性HLA-1型抗原、抗involucrin染色和抗Ⅶ型胶原染色阳性证明新生上皮由移植的人角质细胞形成,抗involucrin染色阳性又证明角质细胞分化成熟有角质层形成,抗Laminin染色、抗Ⅶ型胶原染色阳性提示早期基底膜形成。组织学检查提示第4组新生上皮有许多类似皮钉样结构。结论:培养的角质细胞,成纤维细胞结合纤维蛋白胶移植到创面上后,可以形成复层分化良好、接近正常结构和功能的新生成肤组织。 相似文献
47.
48.
Manna R; Todaro L; Latteri M; Gambassi G; Massi G; Grillo MR; Romito A; Caputo S; Gasbarrini GB 《Rheumatology (Oxford, England)》1997,36(1):124-125
The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but
recently hepatitis C virus (HCV) has been suggested as trigger of
autoimmunity. We report a case of a 26-yr-old patient with purpura due to
leucocytoclastic vasculitis associated with hepatitis C virus infection.
Laboratory findings showed AST, ALT, gamma GT within normal limits,
positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction
for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin
antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic
antibodies with perinuclear pattern were also present. A skin biopsy
specimen of a purpuric lesion showed leucocytoclastic vasculitis with small
vessel thrombosis and perivascular deposition of IgM and fibrinogen on
immunofluorescence study. This case shows a role of HCV in leucocytoclastic
vasculitis; it is possible that this HCV can induce autoimmunity
independently of cryoglobulins and liver involvement.
相似文献
49.
梅尼埃病 (m啨ni埁re’sdisease,MD)的治疗目前仍然是耳科临床上的难题之一 ,主要是因为其病因尚未完全弄清。近年来的耳免疫学研究显示免疫病理学因素在MD的发病中可能起着重要的作用 ,部分患者的发病可能与内耳自身免疫性病变有关。最近 ,我们对 7例 (耳 )慢性化脓性中耳乳突炎(CSOM)伴对侧MD患者行免疫学检查并与 1 0例(耳 )CSOM不伴MD患者进行对照 (对照组 ) ,借以探讨MD发病的免疫学因素。报告如下。1 资料与方法1 .1 临床资料CSOM伴MD组 :7例CSOM伴对侧MD患者 ,男 2例 ,女 5例 ;平均… 相似文献
50.
Clinical, neuropathological, and immunohistochemical (PAP) findings are reported in a 7 month-old girl with Tuberous sclerosis (TS). Polycystic kidneys and massive cardiomegaly constituted the prominent pathological features. The neuropathology of the syndrome was characterized by Megalencephaly, Subependymal giant cell astrocytoma, Very large protoplasmic astrocytes in Golgi-rapid method preparations of cortical tubers and Glial fibrillary acidic protein (GFAP)-negative giant cells in the subependymal nodules as well as in the cortical tubers. The identity of these giant cells is discussed. 相似文献