Department of Pathology, University of São Paulo Medical School, Sao Paulo, Brazil.
Inhal Toxicol. 2011 Jul;23(8):459-67. doi: 10.3109/08958378.2011.582895.
Prolonged exposure to ambient particles is associated with premature mortality due to cardio-respiratory diseases and lung cancer. The size and composition of these particles determine their toxicity, which is aggravated by their long-term retention in the lungs.
To compare the elemental profile of particles retained along the bronchial tree and lymph nodes by combining laser capture microdissection (LCM) and elemental composition analysis through energy dispersive x-ray (EDX) and scanning electron microscopy (SEM).
Twenty-four right lung middle lobes from autopsied cases were obtained from two cities with different pollution backgrounds. Lung samples were collected from three distinct sites within the lung at the time of autopsy: peribronchial tissue, peripheral parenchyma and hilar lymph nodes. Areas of potentially increased particle deposition were microdissected using LCM and analyzed for elemental composition through EDX "allied" with SEM.
Elemental analyses of the particles retained along the bronchial tree showed two groups of distribution: peribronchiolar or lymph node deposition. The elemental profile of peribronchial areas were significantly different between the two cities and were better discriminators of past air pollution exposure.
Our data suggest that particle uptake varies along the bronchial tree and human lung tissue retains particles indicative of regional air pollution background.
长期暴露于环境颗粒物会导致心肺疾病和肺癌导致的过早死亡。这些颗粒的大小和组成决定了它们的毒性，而它们在肺部的长期滞留则加剧了这种毒性。
通过结合激光捕获显微切割（LCM）和能量色散 X 射线（EDX）和扫描电子显微镜（SEM）的元素组成分析，比较支气管树和淋巴结中保留的颗粒的元素分布。
从两个污染背景不同的城市获得了 24 个尸检右肺中叶。在尸检时，从肺的三个不同部位采集肺样本：支气管周围组织、周边实质和肺门淋巴结。使用 LCM 对可能增加颗粒沉积的区域进行显微切割，并通过与 SEM 结合的 EDX 进行元素组成分析。
对支气管周围保留的颗粒进行的元素分析显示出两组分布：支气管周围或淋巴结沉积。两个城市之间支气管周围区域的元素分布明显不同，并且是过去空气污染暴露的更好判别指标。
我们的数据表明，颗粒在支气管树中的吸收情况不同，人体肺组织保留的颗粒表明存在区域性空气污染背景。
