Determination of low-molecular-mass antioxidant concentrations in human respiratory tract lining fluids.

Antioxidants present within lung epithelial lining fluids (ELFs) constitute an initial line of defense against inhaled environmental oxidants such as ozone, nitrogen oxides, and tobacco smoke, but the antioxidant composition of human ELFs is still incompletely characterized. We analyzed ELF concentrations of the low-molecular-mass antioxidants ascorbate, urate, glutathione (GSH), and alpha-tocopherol by obtaining bronchoalveolar lavage (BAL) and nasal lavage fluids from healthy nonsmoking volunteers and compared two different BAL procedures. ELF dilution by the lavage procedures was estimated by measurement of urea in recovered BAL fluids in comparison with those in blood plasma from the same subjects. The results indicated that a recently developed single-cycle BAL procedure minimizes influx of non-ELF urea into the instilled fluid and thus allows for a more accurate determination of ELF antioxidant concentrations. Using this procedure, we determined that bronchoalveolar ELF contains 40 +/- 18 (SD) microM ascorbate, 207 +/- 167 microM urate, 109 +/- 64 microM GSH, and 0.7 +/- 0.3 microM alpha-tocopherol (n = 12 subjects). Similar analysis of nasal lavage fluid yielded nasal ELF levels of 28 +/- 19 microM ascorbate and 225 +/- 105 microM urate (n = 12 subjects), whereas GSH was undetectable (<0.5 microM). Our results demonstrate that ascorbate and urate are major low-molecular-mass ELF antioxidants in both the upper and lower respiratory tract, whereas GSH is present at significant concentrations only in bronchoalveolar ELF.

Perception of fatigue and quality of life in patients with COPD.

INTRODUCTION: Although dyspnea is considered the primary activity-limiting symptom in patients with COPD, other symptoms, such as fatigue, are frequently reported. The purpose of this study was to determine the relationship between fatigue and pulmonary function, exercise tolerance, depression, and quality of life in patients with COPD. METHODS: Forty-one patients (age = 62+/-8 years; FEV1 = 1.08+/-0.55 L; FEV1 percent predicted = 35.8+/-17%) from two sites participated in the study. Spirometric measures of pulmonary function were carried out in each patient. The Multidimensional Fatigue Inventory was used to measure five subscales of fatigue: general, physical and mental fatigue, reduction in activity, and reduction in motivation. The St. George Respiratory Questionnaire, used to measure quality of life, has three subscale dimensions (symptom, activity, and impact), as well as an overall or total quality of life score. Depression was measured with the Centers of Epidemiological Studies Depression Scale. In 19 patients, exercise tolerance was determined with the 6-min walking distance. RESULTS: General fatigue correlated with FEV1, percent predicted (r = -0.32, p < 0.05), exercise tolerance (r = -0.55, p < 0.05), depression (r = 0.44, p < 0.01), and overall quality of life (r = 0.75, p < 0.01). Among the dimensions of fatigue, depression correlated with general and mental fatigue only. Physical dimensions of fatigue correlated with an increase in the severity of pulmonary impairment and reduction in exercise tolerance. The cognitive components of fatigue, such as reduction in motivation and mental fatigue, were not found to be highly correlated with physical dimensions of quality of life. All five subscales of fatigue showed relationship to the functional impact dimension and total impairment score in quality of life. CONCLUSIONS: These data show a relationship between dimensions of fatigue and pulmonary function, exercise tolerance, and quality of life in COPD. Based on these results, fatigue is an important symptom requiring evaluation and management in patients with COPD. These data clarified also the relationship between depression and fatigue in this patient population.

Preparation and analysis of styrene oligomers containing migrates from various polystyrenes used in food packaging.

An oligostyrene-like product (F2L5250) was reported to have estrogen-like activity (statistically significant increases in means for absolute uterine weight and the ratios of the uterine weight to terminal body weight) in juvenile female rats provided a dietary concentration of 100 ppm F2L5250 for four consecutive days. The highest no-effect-level (NOEL) for estrogenic activity was 80 ppm in the diet, corresponding to a daily intake of 13.3 mg F2L5250/kg. Although it is unlikely that such estrogenic tetramers would occur in commercial polystyrene, the Styrene Steering Committee (SSC) of the European Chemical Industry Council (CEFIC) sponsored the current extensive project to address any concern that human consumption of styrene oligomers migrating from polystyrene containers into food, e.g., from packaged yoghurt, or from the use of EPS coffee cups and related products, might affect human health. To ensure confidentiality and compliance with the highest scientific and regulatory standards, the entire project was conducted without knowledge of the oligomer migrates tested, and all activities were managed and audited under a contract between the SSC and a third party, Argus International. This paper describes the preparation and analyses of the 23 representative polystyrenes [9 general purpose polystyrenes (GPPS), 8 high impact polystyrenes (HIPS) and 6 expandable polystyrenes (EPS)] evaluated for estrogenicity in an in vivo uterotrophic assay in immature female rats. The polystyrene samples were chosen to represent food packaging applications. They were obtained from participating European Polystyrene Manufacturers, coded at the TNO Nutrition and Food Research Institute, Utrecht, The Netherlands (TNO) and sent to BASF, Ludwigshafen, Germany for preparation of test bars (GPPS and HIPS) or test foam parts (EPS). The prepared polystyrene test bars or test foam parts were submitted to elution with 50% aqueous (v/v) ethanol for 10 days at 40 degrees C, a procedure which simulates an exposure at ambient temperature for several weeks and represents an exaggeration in comparison with yogurt, for which directive 85/572/EEC1 defines 3% aqueous acetic acid as the official food simulant. To further exaggerate the potential concentration of the possible migrates, the surface/volume ratio selected for elution was the maximum experimentally possible, i.e., approximately 56 dm2/kg food for the GPPS and HIPS bars and approximately 38 dm2/kg food for the EPS foam, representing a multiple of approximately 9 (GPPS and HIPS) and 6 (EPS), times the conventional surface/volume ratio of 6 dm2/kg. These obtained styrene oligomer migrates were then diluted to 25% aqueous (v/v) ethanol, a concentration that could be tolerated by the test animals. After dilution, the low and high concentrations represented multiples of 0.5 and 4.6 (GPPS and HIPS) and 0.5 and 3.2 (EPS) the conventional surface/volume ratio, respectively. These levels simulated daily human consumption of 500 or 5,000 g of food for the GPPS and HIPS samples and of 500 or 3,150 g of food for the EPS samples, respectively. The results of the homogeneity, stability and concentration analyses of the styrene dimers and trimers in the migrates indicated that the concentrations of migrants were highest as the result of 50% aqueous ethanol extraction of HIPS test bars followed by GPPS test bars and EPS test foam parts.

Nd:YAG laser bronchoscopy. Rigid or fiberoptic mode?

One hundred twenty four Nd:YAG laser procedures were performed on 79 patients (age range, 25 to 89 years) over a five-year period at our institution. Over 90 percent of patients had malignant tumors. The fiberoptic bronchoscope (FOB group) was used exclusively during the first two years (61 cases, 32 patients). All except four of these cases utilized conscious sedation and local anesthesia. Subsequent to this, the rigid bronchoscope (RB group) was used as the primary instrument under general anesthesia (51 cases, 42 patients). Twelve cases combined both bronchoscopic modalities (combined group, 12 patients). The percentage improvement in proximal airway lumen diameter post-Nd:YAG laser therapy was significantly greater using the RB (p less than 0.05). For distal lesions, the FOB was superior (p less than 0.05). There was no difference in the complication or survival rates between the groups. Our data suggest that whenever possible, the RB should be used to treat proximal lesions, and the FOB should be used for distal lesions. Both bronchoscopes are often used together. Hence, laser bronchoscopists should be proficient in both bronchoscopic techniques.