Critical conditions for pattern formation and in vitro tubulogenesis driven by cellular traction fields

In vitro angiogenesis assays have shown that tubulogenesis of endothelial cells within biogels, like collagen or fibrin gels, only appears for a critical range of experimental parameter values. These experiments have enabled us to develop and validate a theoretical model in which mechanical interactions of endothelial cells with extracellular matrix influence both active cell migration--haptotaxis--and cellular traction forces. Depending on the number of cells, cell motility and biogel rheological properties, various 2D endothelial patterns can be generated, from non-connected stripe patterns to fully connected networks, which mimic the spatial organization of capillary structures. The model quantitatively and qualitatively reproduces the range of critical values of cell densities and fibrin concentrations for which these cell networks are experimentally observed. We illustrate how cell motility is associated to the self-enhancement of the local traction fields exerted within the biogel in order to produce a pre-patterning of this matrix and subsequent formation of tubular structures, above critical thresholds corresponding to bifurcation points of the mathematical model. The dynamics of this morphogenetic process is discussed in the light of videomicroscopy time lapse sequences of endothelial cells (EAhy926 line) in fibrin gels. Our modeling approach also explains how the progressive appearance and morphology of the cellular networks are modified by gradients of extracellular matrix thickness.     

Stabilization of aminoacyl-tRNA synthetases by sephadex and polyacrylamide gels

Several aminoacyl-tRNA synthetases from the yellow lupin (Lupinus luteus) were stabilized against inactivation during storage at 0–4°, by entrapment in Sephadex or Biogel matrices and drying over P₂O₅. The degree of stabilization depended on the rate of drying of the gel and the pH of the medium and to a lesser extent on the ionic strength and protein concentration. With the exception of prolyl-tRNA synthetase, a greater stability was achieved with those enzymes which were relatively stable to thermal denaturation. Aminoacyl-tRNA synthetases for glutamic acid, glutamine, methionine and arginine, which become inactivated during purification, were considerably stabilized by this procedure.     

抗HPV生物凝胶敷料辅助保妇康栓治疗HPV感染性宫颈炎的临床意义

摘要 目的：探讨抗人乳头瘤病毒（HPV）生物凝胶敷料辅助保妇康栓治疗HPV感染性宫颈炎的临床意义。方法：选择2020年1月至2022年1月在本院接受治疗的HPV感染性宫颈炎患者90例作为研究对象,根据1:1简单分配法把患者分为生物凝胶组与对照组各45例。对照组给予保妇康栓治疗,生物凝胶组在对照组治疗的基础上给予抗HPV生物凝胶敷料治疗,两组都治疗观察1个月。结果：生物凝胶组治疗后的总有效率为100.0 %,高于对照组的86.7 %（P<0.05）。生物凝胶组治疗后HPV转阴率为80.0 %,高于对照组的62.2 %（P<0.05）。治疗后生物凝胶组的的血清白介素-6（IL-6）、C反应蛋白（CRP）、肿瘤坏死因子-α（TNF-α）含量低于治疗前,生物凝胶组低于对照组（P<0.05）。生物凝胶组治疗期间的恶心呕吐、发热、睡眠障碍、乏力等不良反应发生率为6.7 %,低于对照组的28.9 %（P<0.05）。治疗后生物凝胶组生活质量评分高于对照组（P<0.05）。结论：抗HPV生物凝胶敷料辅助保妇康栓治疗HPV感染性宫颈炎有效提升患者的治疗效果及HPV转移率,减少不良反应的发生,可抑制炎症因子的表达,从而持续改善患者的生活质量。