Modeling of Aerosol Transport in Alveolated Airways

肺泡气道中气溶胶传输的建模

• 批准号: 6525333
• 负责人: CHANTAL DARQUENNE
• 金额: $ 18.55万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6525333
• 关键词: aerosols; air pollution; environmental exposure; environmental transport; gravity; lung; mathematical model; model design /development; particle; pulmonary respiration; sedimentation velocity; suspensions

The long-term objective of this study is to better understand the fate of inhaled particles in the human lung. Exposure to particulate matter (PM) has been a major concern in the recent years as more evidence links air pollution and mortality. A better understanding of aerosol deposition (DE) in the lung may also be beneficial in applications such as inhalation drug therapy. Mathematical models are often used to help interpret the experimental studies and to make predictions for cases where experimental data are not available. Aerosol transport in both symmetrical and asymmetrical two-dimensional models of the alveolar zone of the human lung will be simulated ro 0.5 to 5 mum particles is mainly due to gravitational sedimentation. The orientation of the structure with respect to the gravity vector is a major factor affecting DE patterns. CM causes inhaled particles to be irreversibly transferred to the resident air during their transport through the lung. Because of this transfer, some particles that do not deposit on the airway walls remain in suspension in the distal airways at the end of a normal expiration and fail to exit the lung. These particles then penetrate deeper in the lung during the next breath and eventually deposit. Velocity profiles in the alveolar region of the lung are expected to be a major factor that affects CM. The simulations will allow us to isolate their effect and to determine their contribution to overall CM. Finally the effects of extra CM caused by stretch and fold on the alveolar DE of particles in the human lung will be simulated. Stretch and fold refers to the process where, because of non-reversibility of flow in the lung, air streamlines become folded back on themselves, enhancing mixing. The results of this study may provide a link to the mechanisms by which even seemingly modest exposure to PM can cause or exacerbate lung disease. The results will also help to better design spatial targeting of drugs administered by inhalation therapy.

这项研究的长期目标是更好地了解吸入颗粒在人类肺部的命运。近年来，暴露于颗粒物（PM）一直是一个主要问题，因为越来越多的证据将空气污染和死亡率联系起来。 更好地了解肺中的气溶胶沉积（DE）也可能有益于吸入药物治疗等应用。 数学模型通常用于帮助解释实验研究，并在实验数据不可用的情况下进行预测。 将模拟人肺肺泡区的对称和非对称二维模型中的气溶胶传输，因为0.5至5 μ m的颗粒主要是由于重力沉降。 构造相对于重力矢量的方向是影响DE图案的主要因素。 CM导致吸入的颗粒在通过肺部运输期间不可逆地转移到驻留空气中。 由于这种转移，一些没有存款在气道壁上的颗粒在正常呼气结束时在远端气道中保持悬浮状态，并且不能离开肺。 这些微粒在下一次呼吸时会深入肺部并最终存款。 肺的肺泡区域中的速度曲线预计是影响CM的主要因素。 模拟将使我们能够隔离它们的影响，并确定它们对整体CM的贡献。 最后模拟了拉伸和折叠引起的额外CM对人肺中颗粒物肺泡DE的影响。 拉伸和折叠是指由于肺中流动的不可逆性，空气流线自身折回，从而增强混合的过程。 这项研究的结果可能提供了一个链接的机制，即使是看似温和的暴露于PM可以导致或加剧肺部疾病。 这些结果也将有助于更好地设计吸入治疗药物的空间靶向。