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Exhaled isoprene and acetone in newborn infants and in children with diabetes mellitus.

A new analytical method gas chromatography combined with UV spectrophotometry was used to measure isoprene and acetone in expired breath collected from four different groups of children: 1) healthy newborn babies, 2) healthy preschool children, 3) healthy school children, and 4) diabetic children in different metabolic states. Both isoprene and acetone could readily be determined in one single analysis of a 250-mL air sample. Newborn babies during the first postnatal week had undetectable or very low levels of isoprene in their expired air irrespective of catabolic or anabolic state. Breath isoprene increased with age, and healthy school children had higher levels than did healthy preschool children. No significant differences in breath isoprene were found between healthy and diabetic children. Breath acetone was found to correlate with metabolic state both in newborn babies and in diabetic children. These findings illustrate the potential use of a new technique for breath analysis in children with metabolic disturbances.

Acetone↗

Women and lung cancer: waiting to exhale.

Lung cancer is now the leading cause of cancer deaths among women. In the United States, 64,300 women are expected to die of lung cancer in 1996. Smoking is responsible for about 80% of lung cancer cases. Unfortunately, the prevalence of smoking among women remains unacceptably high at about 22% and is expected to surpass the rate in men by the year 2000. Smoking rates are highest among young girls and the less educated. Whether lung cancer represents a different disease in women than in men is unclear. Data are conflicting regarding the magnitude of the relative risk of developing lung cancer due to smoking between the genders. There appears to be a difference in the relative distribution of lung cancer histologic features between men and women that is not explained entirely by differences in smoking patterns. Women who smoke appear to be at higher risk of developing small cell lung cancer than squamous cell lung cancer, whereas men who smoke have a similar risk for the two histologic conditions. Furthermore, women smokers are more likely to develop adenocarcinoma of the lung, and estrogens may play a causative role in this phenomenon. Data are unclear regarding whether the outcome of lung cancer treatment differs between genders. Solutions to the lung cancer epidemic among US women include (1) prevention of the disease by reducing smoking rates, (2) improving early detection methods, and (3) exploring new therapeutic strategies.

Female↗

Analysis of tracheal sounds during forced exhalation in asthma patients and normal subjects: bronchodilator response effect.

PURPOSE: During the past 10 years, the acoustic analysis of breath sounds has been used as a diagnostic tool in patients suffering from obstructive respiratory diseases. Acoustic analysis might be able to monitor the response to bronchodilator therapy in a clinical setting. So far, few studies have been carried out in asthmatic patients. To assess the responses of a sampling of asthma patients to an inhaled bronchodilator (terbutaline) by means of spectral analysis of the tracheal sound performed during forced expiratory maneuvers. MATERIAL AND METHODS: Seventeen nonsmoking asthma patients (9 were male, 8 were female) who had been suffering from the disease for > or = 15 years were included in the study, as were 15 normal subjects (7 were male, 8 were female). The average age (+/- SD) was 56.5 +/- 15.2 years (FVC, 2.7 +/- 0.9 L [63.4%]; FEV1, 1.5 +/- 0.6 L [53.0%]). The tracheal sounds were collected during three forced expiratory maneuvers with a sampling frequency of 5,000 Hz and were analyzed by applying a 16-parameter autoregressive model. RESULTS: The centroid frequency decreased after the bronchodilator was given at different flow segments between 1.2 and 0.4 L/s, with significant changes between 0.6 and 0.4 L/s. CONCLUSIONS: Patients with asthma showed changes in the spectral acoustic analysis frequencies after the administration of a bronchodilator drug (terbutaline) during forced expiratory maneuvers.

Adolescent↗