Study of thiobarbituric reactive substances and total reduced glutathione as indices of oxidative stress in chronic smokers with and without chronic obstructive pulmonary disease.

BACKGROUND: The imbalance between oxidants and antioxidants is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). METHODS: Biomarkers of lipid oxidation such as thiobarbituric reactive substances (TBARs), total reduced glutathione (GSH) were estimated in chronic smokers with and without COPD, and non-smokers. RESULTS: The following subjects (all males) were studied: (i) chronic smokers (32.5 +/- 8.6 pack years) with stable COPD (n = 20; mean age 47.2 +/- 7.8 years); (ii) chronic smokers (6.3 +/- 1.9 pack years) without COPD (n = 20; mean age 35.3 +/- 4.5 years); and (iii) non-smokers (n = 20; mean age 37.5 +/- 5.5 years). The mean TBARs levels (nmol of malondialdehyde per ml of plasma) were higher among smokers with COPD (5.72 +/- 1.02) when compared with smokers without COPD (4.85 +/- 0.97) and non-smokers (2.58 +/- 0.56) (p < 0.001). The mean GSH levels (micromol/mg of protein) were significantly higher in non-smokers (0.163 +/- 0.113) compared to smokers with COPD (0.083 +/- 0.05) and those without COPD (0.050 +/- 0.051) (p < 0.001). There was no statistically significant difference in the plasma GSH levels among smokers with and without COPD (p > 0.05). CONCLUSIONS: Our observations demonstrate increased lipid peroxidation because of oxidative stress due to smoking.

Eosinophilic pleural effusion and presence of filariform larva of Strongyloides stercoralis in a patient with metastatic squamous cell carcinoma deposits in the pleura.

A 58-year-old, human immunodeficiency virus (HIV) negative, male farmer presented with a right-sided hemorrhagic, exudative, eosinophilic, rapidly reaccumulating pleural effusion. Pleural biopsy revealed secondary deposits from a squamous cell carcinoma. Wet mount film of pleural fluid unexpectedly showed filariform larvae of Strongyloides stercoralis. Our observation suggests that strongyloidiasis should be considered as the etiological cause for pleural effusion of obscure etiology. The threshold for suspicion should be high if the pleural effusion is exudative and eosinophil rich.