Smoking cessation and bronchial epithelial remodelling in COPD: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Chronic Obstructive Pulmonary Disease (COPD) is associated with bronchial epithelial changes, including squamous cell metaplasia and goblet cell hyperplasia. These features are partially attributed to activation of the epidermal growth factor receptor (EGFR). Whereas smoking cessation reduces respiratory symptoms and lung function decline in COPD, inflammation persists. We determined epithelial proliferation and composition in bronchial biopsies from current and ex-smokers with COPD, and its relation to duration of smoking cessation.</p> <p>Methods</p> <p>114 COPD patients were studied cross-sectionally: 99 males/15 females, age 62 ± 8 years, median 42 pack-years, no corticosteroids, current (n = 72) or ex-smokers (n = 42, median cessation duration 3.5 years), postbronchodilator FEV₁63 ± 9% predicted. Squamous cell metaplasia (%), goblet cell (PAS/Alcian Blue⁺) area (%), proliferating (Ki-67⁺) cell numbers (/mm basement membrane), and EGFR expression (%) were measured in intact epithelium of bronchial biopsies.</p> <p>Results</p> <p>Ex-smokers with COPD had significantly less epithelial squamous cell metaplasia, proliferating cell numbers, and a trend towards reduced goblet cell area than current smokers with COPD (p = 0.025, p = 0.001, p = 0.081, respectively), but no significant difference in EGFR expression. Epithelial features were not different between short-term quitters (<3.5 years) and current smokers. Long-term quitters (≥3.5 years) had less goblet cell area than both current smokers and short-term quitters (medians: 7.9% vs. 14.4%, p = 0.005; 7.9% vs. 13.5%, p = 0.008; respectively), and less proliferating cell numbers than current smokers (2.8% vs. 18.6%, p < 0.001).</p> <p>Conclusion</p> <p>Ex-smokers with COPD had less bronchial epithelial remodelling than current smokers, which was only observed after long-term smoking cessation (>3.5 years).</p> <p>Trial registration</p> <p>NCT00158847</p

Multidrug resistance-associated protein-1 (MRP1) genetic variants, MRP1 protein levels and severity of COPD

<p>Abstract</p> <p>Background</p> <p>Multidrug resistance-associated protein-1 (MRP1) protects against oxidative stress and toxic compounds generated by cigarette smoking, which is the main risk factor for chronic obstructive pulmonary disease (COPD). We have previously shown that single nucleotide polymorphisms (SNPs) in <it>MRP1 </it>significantly associate with level of FEV₁in two independent population based cohorts. The aim of our study was to assess the associations of <it>MRP1 </it>SNPs with FEV₁level, MRP1 protein levels and inflammatory markers in bronchial biopsies and sputum of COPD patients.</p> <p>Methods</p> <p>Five SNPs (rs212093, rs4148382, rs504348, rs4781699, rs35621) in <it>MRP1 </it>were genotyped in 110 COPD patients. The effects of <it>MRP1 </it>SNPs were analyzed using linear regression models.</p> <p>Results</p> <p>One SNP, rs212093 was significantly associated with a higher FEV₁level and less airway wall inflammation. Another SNP, rs4148382 was significantly associated with a lower FEV₁level, higher number of inflammatory cells in induced sputum and with a higher MRP1 protein level in bronchial biopsies.</p> <p>Conclusions</p> <p>This is the first study linking <it>MRP1 </it>SNPs with lung function and inflammatory markers in COPD patients, suggesting a role of <it>MRP1 </it>SNPs in the severity of COPD in addition to their association with MRP1 protein level in bronchial biopsies.</p

Plant Networks for Processing Recyclable Materials

10.1287/msom.2013.0437Manufacturing and Service Operations Management154670-688MSOM

Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 2

https://egrove.olemiss.edu/aicpa_sop/1662/thumbnail.jp

Induction Patterns of an Extensin Gene in Tobacco upon Nematode Infection.

When sedentary endoparasitic nematodes infect plants, they induce complex feeding sites within the root tissues of their host. To characterize cell wall changes induced within these structures at a molecular level, we studied the expression of an extensin gene (coding for a major structural cell wall protein) in nematode-infected tobacco roots. Extensin gene expression was observed to be induced very early upon infection. This induction was weak, transient, and probably due to wounding during penetration and migration of the tobacco cyst nematode Globodera tabacum ssp solanacea-rum. In contrast, high extensin gene expression was observed during the whole second larval stage (an ~2-week-long phase of establishment of the feeding site) of the root knot nematode Meloidogyne javanica. During later stages of this interaction, expression gradually decreased. Extensin gene expression was found in at least three different tissues of the gall. We propose that distinct mechanisms lead to induced expression in these different cell types. The significance of these results for the understanding of plant-nematode interactions as well as the function of structural cell wall proteins, such as extensin, is discussed

Relapse in FEV1 Decline After Steroid Withdrawal in COPD

BACKGROUND: We previously observed that 30 months of inhaled corticosteroid (ICS) treatment can attenuate FEV1 decline in COPD, but it is unclear whether withdrawal induces a relapse. We hypothesized that FEV1 decline, airway hyperresponsiveness (AHR), and quality of life (QOL) deteriorate after ICS cessation even after prolonged use. METHODS: One hundred fourteen patients with moderate to severe COPD finished randomized 6-month or 30-month treatment with fluticasone (500 mu g bid), 30-month treatment with fluticasone and salmeterol (500/50 mu g bid), or placebo (first part of the Groningen and Leiden Universities Corticosteroids in Obstructive Lung Disease [GLUCOLD] study [GL1]). The subsequent 5 years, patients were prospectively followed annually, treated by their physician (GLUCOLD follow-up study [GL2]). Postbronchodilator FEV1, AHR, and QOL were initially recorded at baseline, at 30 months (GL1), and annually during GL2. Analysis was performed by linear mixed-effects models. RESULTS: Among 101 adherent patients during GL1, 79 patients started and 58 completed GL2. Patients using ICSs during GL1, but only using ICSs 0% to 50% of the time during GL2 (n = 56 of 79), had significantly accelerated annual FEV1 decline compared with GL1 (difference GL2-GL1 [95% CI]: 30-month treatment with fluticasone and salmeterol, -68 mL/y [-112 to -25], P = .002; 30-month treatment with fluticasone, -73 mL/y [-119 to -26], P = .002), accompanied by deterioration in AHR and QOL. CONCLUSIONS: ICS discontinuation aft er 30 months in COPD can worsen lung function decline, AHR, and QOL during 5-year follow-up. This suggests that ICS treatment lacks sustained disease-modifying effect after treatment cessation