存在扩散和吸收屏障时抗生素通过生物膜的扩散
Diffusion of antibiotics through a biofilm in the presence of diffusion and absorption barriers
摘要：
我们提出了一个模型的抗生素扩散通过细菌生物膜时，扩散和/或吸收障碍的生物膜中发展。这个模型的思想是：我们推导出的细节中的直接实验研究是困难的，在外部区域的探测扩散的基础上，在介质中的扩散过程。由于生物膜具有凝胶状稠度，我们假设可能发生生物膜中颗粒的亚扩散。为了描述这个过程，我们使用一个分数次扩散吸收方程与可调的反常扩散指数。在生物膜的边界处的边界条件是通过离散晶格上的粒子随机游走模型导出的，该离散晶格导致涉及分数时间导数的表达式。我们表明，通过生物膜扩散的物质总量的时间演变明确取决于生物膜中是否有抗生素吸收。该事实用于实验检查生物膜中的抗生素吸收以及生物膜参数是否随时间变化。基于上述物理特性，我们提出了抗生素在生物膜中扩散的四阶段模型。生物学解释的阶段，特别是它们与细菌防御机制的关系，进行了讨论。将理论结果与环丙沙星通过铜绿假单胞菌生物膜扩散的经验结果以及环丙沙星和庆大霉素通过奇异变形杆菌生物膜扩散的经验结果进行了比较。
英文摘要：
We propose a model of antibiotic diffusion through a bacterial biofilm when diffusion and/or absorption barriers develop in the biofilm. The idea of this model is: We deduce details of the diffusion process in a medium in which direct experimental study is difficult, based on probing diffusion in external regions. Since a biofilm has a gel-like consistency, we suppose that subdiffusion of particles in the biofilm may occur. To describe this process we use a fractional subdiffusion-absorption equation with an adjustable anomalous diffusion exponent. The boundary conditions at the boundaries of the biofilm are derived by means of a particle random walk model on a discrete lattice leading to an expression involving a fractional time derivative. We show that the temporal evolution of the total amount of substance that has diffused through the biofilm explicitly depends on whether there is antibiotic absorption in the biofilm. This fact is used to experimentally check for antibiotic absorption in the biofilm and if the biofilm parameters change over time. We propose a four-stage model of antibiotic diffusion in biofilm based on the mentioned above physical characteristics. The biological interpretation of the stages, in particular their relation with the bacterial defence mechanisms, is discussed. Theoretical results are compared with empirical results of ciprofloxacin diffusion through Pseudomonas aeruginosa biofilm, and ciprofloxacin and gentamicin diffusion through Proteus mirabilis biofilm.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
