NEJM Audio Summary - Oct 27, 2011

今回からポッドキャストの聴き方を変えてみる。今まではランニングしながらポッドキャスト全体を聴いていた。１回のランで２回聴けてたのが、１回半になってもリスニングの能力向上の実感が湧かない。脚力のようには聴解力は身につかないのである。そこで、同じ材料を聴く回数を増やすために、関心のある記事を繰り返し聴く方法に切り替えてみることにした。

Excerpted Script

00:54 | "Small-Airway Obstruction and Emphysema in Chronic Obstructive Pulmonary Disease" by John McDonough from St. Paul's Hospital, Vancouver, British Columbia, Canada. Patients with COPD have increased peripheral airway resistance. Using CT to compare the number of airways measuring 2.0 to 2.5 mm in 78 patients who had various stages of COPD. This study determined whether there was a relationship between small-airway obstruction and emphysematous destruction in COPD. The number of airways measuring 2.0 to 2.5 mm in diameter was reduced in patients with Global Initiative for Chronic Obstructive Lung disease (GOLD) scale stage 1, 2, 3 and 4 disease. MicroCT of isolated samples of lungs removed from patients with GOLD stage 4 disease showed a reduction of 81 to 99.7% in the total cross-sectional area of terminal bronchioles and a reduction of 72 to 89% in the number of terminal bronchioles. A comparison of the number of terminal bronchioles and dimensions at different levels of emphysematous destruction showed that the narrowing and loss of terminal bronchioles preceded emphysematous destruction in COPD. These results show that narrowing and disappearance of small conducting airways before the onset of emphysematous destruction can explain the increased peripheral airway resistance reported in COPD.
02:30 | In EDITORIAL, Wayne Mitzner from Johns Hopkins Bloomberg School of Public Health, Baltimore, writes this study raises key issues related to the timeline of the pathology in COPD, particularly with regard to the interaction between the peripheral airways and parenchyma. Given this uncertainty regarding the pathologic progression, it may be time to think about reconsidering the definition of emphysema. A new definition will clearly need to include more about the involvement of small airways beyond the simple absence of obvious fibrosis. On the basis of the work of McDonough and colleagues, the permanent enlargement of the distal airspaces may serve only as a structural biomarker, being a secondary result of small-airway inflammation and destruction.    (321 words/ 45-201sec = 131wpm) 

Collocation

• determine whether
• relationship between/with
• analysis/study/patient/result/data show
• after/with/of/before the onset

Refered Blogs

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• 六号通り診療所所長のブログ「肺気腫は何故起こるのか？」