In the present study, we hypothesized that exhaustive exercise in patients with chronic obstructive pulmonary disease (COPD) results in glutathione oxidation and lipid peroxidation and that xanthine oxidase (XO) contributes to free radical generation during exercise. COPD patients performed incremental cycle ergometry until exhaustion with (n = 8) or without (n = 8) prior treatment with allopurinol, an XO inhibitor. Reduced (GSH) and oxidized glutathione (GSSG) and lipid peroxides [malondialdehyde (MDA)] were measured in arterial blood. In nontreated COPD patients, maximal exercise (approximately 75 W) resulted in a significant increase in the GSSG-to-GSH ratio (4. 6 +/- 0.9% at rest vs. 9.3 +/- 1.7% after exercise). In nontreated patients, MDA increased from 0.68 +/- 0.08 nmol/ml at rest up to 1. 32 +/- 0.13 nmol/ml 60 min after cessation of exercise. In contrast, in patients treated with allopurinol, GSSG-to-GSH ratio did not increase in response to exercise (5.0 +/- 1.2% preexercise vs. 4.6 +/- 1.1% after exercise). Plasma lipid peroxide formation was also inhibited by allopurinol pretreatment (0.72 +/- 0.15 nmol/ml preexercise vs. 0.64 +/- 0.09 nmol/ml 60 min after exercise). We conclude that strenuous exercise in COPD patients results in blood glutathione oxidation and lipid peroxidation. This can be inhibited by treatment with allopurinol, indicating that XO is an important source for free radical generation during exercise in COPD.

Exposure-response relationships for endotoxin as measured in dust and longitudinal decline in lung function were studied. A cohort of 171 pig farmers was followed over a 3-yr period. Long-term average exposure to dust and endotoxin was determined by personal monitoring in summer and winter, using data on farm characteristics and activities. Mean decline in FEV1 was 73 ml/yr and in FVC 55 ml/ yr. Long-term average exposure to dust was 2.63 mg/m3 (geometric SD [GSD] 1.30), and to endotoxin, 105 ng/m3 (GSD 1.5). Annual decline in FEV1 was significantly associated with endotoxin exposure. An increase in exposure with a factor 2 was associated with an extra decline of FEV1 of 19 ml/yr.

No abstract

The Nijmegen Questionnaire was introduced over 30 years ago as a screening tool to detect patients with hyperventilation complaints that could benefit from breathing regulation through capnographic feedback [1]. It was validated against the Hyperventilation Provocation Test [2], on the assumption at the time that hypocapnia was causally related to complaints. In later studies, the correlation between Nijmegen Questionnaire scores and carbon dioxide tensions appeared highly variable. The diagnosis of hyperventilation syndrome (HVS) was questioned and slowly disappeared. Nevertheless, the Nijmegen Questionnaire has remained in use and we have noticed even a recent increase in studies in clinical medicine as well as requests for permission to use the Nijmegen Questionnaire in new studies. We would like to formally declare here that the Nijmegen Questionnaire is not copyrighted and is free to use. It has been or will be translated, as far as we know, into Greek, Farsi, Finnish, Norwegian, Swedish, Spanish, Filipino and Chinese. However, the validity of the Nijmegen Questionnaire is often a point of discussion and we would like to make a few comments on that issue [3].

Background-Patients with a poor perception of their symptoms of asthma seem to have an increased risk of an asthma attack. The influence of factors such as airway calibre, bronchial hyperresponsiveness, age and sex on the "perceptiveness" of a patient are poorly understood. It is of clinical importance to identify patients who are likely to have a poor perception of their symptoms. We have studied the perception of bronchoconstriction by asthmatic patients during a histamine provocation test and analysed the influence of bronchial obstruction, hyperresponsiveness, sex, and age. We were particularly interested to establish whether there was any diVerence in perception between subjects with a greater or lesser severity of asthma (expressed as bronchial obstruction, hyperresponsiveness). with a low degree of "perceptiveness" for bronchoconstriction. This suggests that patients with a more severe degree of asthma either show adaptation of "perceptiveness" for airway obstruction or that low perceptiveness leads to more severe asthma. (Thorax 1999;54:15-19) Methods-One