Abrami Michela, Maschio Massimo, Conese Massimo, Confalonieri Marco, Gerin Fabio, Dapas Barbara, Farra Rossella, Adrover Alessandra, Torelli Lucio, Ruaro Barbara, Grassi Gabriele, Grassi Mario
Department of Engineering and Architecture, University of Trieste, Via Valerio 6/A, I-34127, Trieste, Italy.
Institute for Maternal and Child Health, IRCCS Burlo Garofolo, Via Dell'Istria, 65, I-34137, Trieste, Italy.
Respir Med. 2021 Nov-Dec;189:106623. doi: 10.1016/j.rmed.2021.106623. Epub 2021 Sep 25.
As most cystic fibrosis (CF) patients progress to respiratory failure, lung functionality assessment is pivotal. We previously developed a test that indirectly monitors airways (inflammation/functional test) by measuring the spin-spin relaxation time (T) of the water hydrogens present in CF sputum. Here the T significance in the monitoring of CF lung disease was further investigated by studying the correlation of T with: 1) sputum viscoelasticity, 2) mucociliary clearability index (MCI)/cough clearability index (CCI) and 3) sputum average mesh-size.
Sputum samples from 25 consenting CF subjects were analyzed by rheology tests (elastic modulus G and zero shear viscosity η) and Low Field Nuclear Magnetic (LF-NMR) resonance (T). MCI/CCI were calculated from the rheological parameters. The average mesh-size (ξ) of the sputum structure was then evaluated by rheology/LF-NMR, together with FEV for each patient.
There was an inverse correlation between G and η versus T, indicating that a worsening of the lung condition (T-FEV drop) is paralleled by an increase in sputum viscoelasticity (G and η) favoring mucus stasis/inflammation. A direct correlation was also observed between T and MCI/CCI, showing that T provides information as to airway mucus clearing. Moreover, there was a direct correlation between T and the average sputum mesh size (ξ).
We demonstrated a correlation between T (measured in CF patient's sputum) and the sputum viscoelasticity/average mesh-size and with MCI/CCI, parameters related to airway mucus clearing. Thus, the present data strengthen the potential of our test to provide indirect monitoring of airway disease course in CF patients as T depends on mucus solid concentration and nanostructure.
由于大多数囊性纤维化（CF）患者会发展为呼吸衰竭，因此肺功能评估至关重要。我们之前开发了一种测试方法，通过测量CF痰液中氢质子的自旋-自旋弛豫时间（T₂）来间接监测气道（炎症/功能测试）。在此，通过研究T₂与以下因素的相关性，进一步探讨T₂在CF肺部疾病监测中的意义：1）痰液粘弹性，2）黏液纤毛清除指数（MCI）/咳嗽清除指数（CCI），以及3）痰液平均网眼尺寸。
对25名同意参与的CF患者的痰液样本进行流变学测试（弹性模量G和零剪切粘度η）和低场核磁共振（LF-NMR）（T₂）分析。根据流变学参数计算MCI/CCI。然后通过流变学/LF-NMR评估痰液结构的平均网眼尺寸（ξ），同时测量每位患者的第一秒用力呼气容积（FEV₁）。
G和η与T₂呈负相关，表明肺部状况恶化（T₂-FEV₁下降）与痰液粘弹性增加（G和η）同时出现，这有利于黏液淤滞/炎症。T₂与MCI/CCI之间也存在正相关，表明T₂可提供气道黏液清除方面的信息。此外，T₂与痰液平均网眼尺寸（ξ）之间存在正相关。
我们证明了T₂（在CF患者痰液中测量）与痰液粘弹性/平均网眼尺寸以及与MCI/CCI之间存在相关性，这些参数与气道黏液清除有关。因此，目前的数据强化了我们的测试在间接监测CF患者气道疾病进程方面的潜力，因为T₂取决于黏液固体浓度和纳米结构。
