European journal of respiratory diseases. Supplement最新文献

Skin-tests with the prick technique were made on 121 dairy farmers with allergic rhinitis and/or asthma (symptomatic subjects), 64 dairy farmers without respiratory symptoms (asymptomatic subjects), and 26 non-farming controls. The antigen panel consisted of the storage mites Acarus siro, Lepidoglyphus destructor, and Tyrophagus putrescentiae, as well as other work-related allergens (cereal grains, animal epithelia, fungi and yeasts), and common allergens (house dust mite, pollens). Mean areas of weals formed by individual allergens were adjusted by analysis of covariance for age, sex, and atopic background (past or present atopic dermatitis including infantile eczema). Adjusted mean weal areas for almost all allergens, except pollens and few other allergens, were significantly larger in farmers than in non-farming controls. In contrast, only skin reactions to cow dander, to a non-dialyzed crude preparation of fodder yeast Candida utilis, and to Candida albicans distinguished symptomatic subjects from asymptomatic ones. Stepwise discriminant analysis, in which reactions to all allergens as well as age, sex, and atopy were taken into account simultaneously, revealed that reactions to a dialysed preparation of fodder yeast best distinguished symptomatic farmers from asymptomatic ones. C. utilis and C. albicans may be cross-reactive. The results imply that skin tests alone are of limited value in the search for work-related causes of rhinitis or asthma among dairy farmers. Our study confirms the importance of cow dander as an occupational allergen in dairy farming. Fodder yeast seems to be another important occupational sensitizer.

Clara cells are non-ciliated epithelial cells located mainly in small conducting airways. They give rise to ciliated cells and are also thought to secrete components of the extracellular layer lining small conducting airways. Using morphometry and electron microscopy we have shown that secretion by Clara cells in rats is stimulated by a beta-adrenergic agent, by prostacyclin and by large tidal volumes. The effect of large tidal volume ventilation breathing on secretion is blocked by indomethacin (an inhibitor of prostaglandin synthesis), but it is not blocked by cholinergic blockade or by beta- or alpha-adrenoceptor antagonists. More recently we have shown that Clara cells in rats are immature at birth, rapidly gain maturity within the first postnatal week and that maternal undernutrition delays the attainment of maturity; glucagon given intraperitoneally to the rat fetus just before term accelerates the attainment of maturity; glucagon given intraperitoneally to the rat fetus just before term accelerates the attainment of maturity.

The reproducibility of the early asthmatic response after bronchial challenge with cladosporium herbarum was studied in 5 adult asthmatics. Four bronchial challenges were done in randomized order with an interval of one week. The four challenges were: cladosporium herbarum, cladosporium herbarum, histamine and saline. The bronchial challenges were done double-blind. Cladosporium herbarum was inhaled in the following concentrations (w/v): 1:100000, 1:10000, 1:1000 and up to 1:100. Histamine was inhaled in the following concentrations: 0.3, 0.6, 1.2 and up to 2.4 mg/ml FEV1 was measured before every inhalation and 2, 5, 10 min after. If FEV1 dropped greater than 20% after inhalation, the challenge was assessed as positive and the provocation on that day was stopped. The provocation was assessed as negative if this fall was not seen after the fourth inhalation. Two patients with positive skin test to cladosporium herbarum had reproducible early asthmatic response after inhalation of the antigen, they reacted to inhaled histamine and one of them presented an early asthmatic response after inhalation of saline. Three patients with negative skin test to cladosporium herbarum had an early asthmatic response after inhalation of the antigen on two out of six provocations, a response which was not reproducible. None of the three responded to saline. It is concluded that inhalation challenge with cladosporium herbarum may be more confusing than helpful in the diagnosis of early asthmatic response to this antigen, as patients with negative history and negative skin test sometimes present a positive bronchial challenge.

The effect of slow digitalization was tested by radioisotopic angiocardiography in 33 patients with stable and compensated chronic obstructive pulmonary disease (COPD); most of these had severe chronic respiratory failure (CRF). After a 10 days course of digoxin, 0.25 mg/die per os, both the left ventricular ejection fraction (LVEF) and the peak ejection rate (PER), initially slightly abnormal, improved significantly (t = -3.474, p less than 0.005; t = -2.438, p less than 0.025), while right ventricular ejection fraction (RVEF) and peak filling rate (PFR) did not. Ventricular diastolic interdependence and abnormal myocardial calcium kinetic are likely to account for PFR behaviour. Digoxin effects upon RVEF and LVEF suggest that the right ventricular systolic function is to some extent independent from the left one when blood gas derangement and abnormal thoracopulmonary mechanics are the major determinant of right ventricular afterload. The lack of significant correlation between digoxin effects on right and left ventricular function indices confirms this hypothesis. Digoxin can improve the left ventricular ejection phase indices, when these are initially abnormal, while its effect on RVEF is unpredictable.