Islam Mohammad S, Saha Suvash C, Sauret Emilie, Gemci Tevfik, Yang Ian A, Gu Y T
School of Chemistry, Physics & Mechanical Engineering, Queensland University of Technology (QUT), 2 George Street, GPO Box 2434, Brisbane, QLD 4001, Australia.
School of Chemistry, Physics & Mechanical Engineering, Queensland University of Technology (QUT), 2 George Street, GPO Box 2434, Brisbane, QLD 4001, Australia.
J Biomech. 2017 Nov 7;64:16-25. doi: 10.1016/j.jbiomech.2017.08.028. Epub 2017 Sep 5.
To understand how to assess optimally the risks of inhaled particles on respiratory health, it is necessary to comprehend the uptake of ultrafine particulate matter by inhalation during the complex transport process through a non-dichotomously bifurcating network of conduit airways. It is evident that the highly toxic ultrafine particles damage the respiratory epithelium in the terminal bronchioles. The wide range of in silico available and the limited realistic model for the extrathoracic region of the lung have improved understanding of the ultrafine particle transport and deposition (TD) in the upper airways. However, comprehensive ultrafine particle TD data for the real and entire lung model are still unavailable in the literature. Therefore, this study is aimed to provide an understanding of the ultrafine particle TD in the terminal bronchioles for the development of future therapeutics. The Euler-Lagrange (E-L) approach and ANSYS fluent (17.2) solver were used to investigate ultrafine particle TD. The physical conditions of sleeping, resting, and light activity were considered in this modelling study. A comprehensive pressure-drop along five selected path lines in different lobes was calculated. The non-linear behaviour of pressure-drops is observed, which could aid the health risk assessment system for patients with respiratory diseases. Numerical results also showed that ultrafine particle-deposition efficiency (DE) in different lobes is different for various physical activities. Moreover, the numerical results showed hot spots in various locations among the different lobes for different flow rates, which could be helpful for targeted therapeutical aerosol transport to terminal bronchioles and the alveolar region.
为了理解如何最佳地评估吸入颗粒物对呼吸系统健康的风险，有必要了解在通过非二叉分支的气道网络进行的复杂传输过程中，吸入的超细颗粒物的摄取情况。显然，高毒性的超细颗粒会损害终末细支气管中的呼吸道上皮。计算机模拟方面广泛可用的数据以及肺胸外区域有限的现实模型，增进了我们对超细颗粒在上呼吸道中的传输和沉积（TD）的理解。然而，文献中仍然没有针对真实完整肺模型的全面超细颗粒TD数据。因此，本研究旨在了解超细颗粒在终末细支气管中的TD情况，以促进未来治疗方法的发展。采用欧拉 - 拉格朗日（E - L）方法和ANSYS fluent（17.2）求解器来研究超细颗粒TD。本模拟研究考虑了睡眠、休息和轻度活动的身体状况。计算了沿不同肺叶中五条选定路径线的综合压降。观察到压降的非线性行为，这可能有助于呼吸系统疾病患者的健康风险评估系统。数值结果还表明，不同身体活动下，不同肺叶中超细颗粒的沉积效率（DE）不同。此外，数值结果显示了不同流速下不同肺叶中不同位置的热点，这可能有助于将靶向治疗性气溶胶输送到终末细支气管和肺泡区域。
