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Exposure of guinea‐pigs to aerosols of platelet activating factor (PAF) (0.01 to 100 μg ml−1) induced a dose‐dependent increased incidence of eosinophils in bronchoalveolar lavage fluid (BAL) at 48 h. Total leucocyte numbers and the percentages of lymphocytes and neutrophils were unchanged in BAL fluid. Increased numbers of eosinophils were detected in BAL 1 h after exposure to PAF but eosinophilia was not maximal until 48 h. One week after exposure to PAF, the percentage of eosinophils in BAL was within the normal range. Depletion of circulating platelets or neutrophils by intravenous injection of specific antisera did not modify accumulation of eosinophils in the airway lumen following inhalation of PAF (10 μg ml−1). PAF‐induced pulmonary airway eosinophil accumulation was inhibited by treatment with SDZ 64–412, a selective PAF‐antagonist, whether the compound was administered before, or 30 min after, inhalation of PAF. Pulmonary airway eosinophil accumulation due to inhaled PAF (10 μg ml−1) was inhibited by prior treatment with aminophylline, cromoglycate, ketotifen, dexamethasone and AH 21–132. Pulmonary airway eosinophil accumulation due to inhaled PAF (10 μg ml−1) was not inhibited by prior treatment with indomethacin, salbutamol or mepyramine.

This paper describes two Canadian aboriginal organizations which have attempted a second-order change, a transformation of their belief system, to make their organizations operate in a manner consistent with traditional aboriginal beliefs, values, and customs. One organization completed a successful change, the other organization's change process was abandoned after 2 years. The process of organizational change followed by the two organizations illustrates the link between interpretive schemes, organizational actions, and organizational structures. The process which focused primarily on the link between the aboriginally-based interpretive scheme and actions proved more effective than the process that linked the structure and the interpretative scheme. For the successful organization, the process of organizational transformation was shown to be incremental, iterative, multifaceted and required a lengthy period of time to complete. During the early stages of process of change, both old and new interpretative schemes were present within the organization. The process of organizational change then became a dialectic involving the old and the new. As a critical mass of people began to adopt the new interpretative scheme, the dialectic focused on different ways of implementing the new scheme. Leaders, critical to the process, had two essential tasks: enabling or permitting the presentation of new interpretative schemes and keeping the dialectic going for a sufficient period of time to ensure the emergence of a interpretative scheme shared by a critical mass of organizational members.

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Abstract-IntraperitoneaI (i.p.) injection of platelet activating factor (PAF) in guinea pigs caused a dose-related increase in the number of eosinophils recovered from bronchoalveolar lavage fluid (BALF). The prevalence of eosinophils in BALF had significantly increased within 1 hr of i.p. injection of PAF (10 /-'g/animal) and was maximal after 24 hr. Subcutaneous osmotic mini-pumps were used to administer drugs for 5 days prior to i.p. injection of PAF (10 ,ug/animal) and for the subsequent 24 hr. The percentage increase of eosinophils in BALF, due to PAF, was inhibited in animals treated with dexamethasone, aminophylline, cromoglycate, tranilast or ketotifen, but not in animals treated with oxatomide, azelastine, amlexanox, ibudilast or AA-861. These results suggest that inhibition of pulmonary eosinophilia may be a necessary property of prophylactic anti-asthma drugs and provide indirect evidence favoring a role for PAF in eosinophilia of asthma.

Subcutaneous or intraperitoneal injection of recombinant human granulocyte-macrophage colony-stimulating factor, interleukin 3, or mouse tumour necrosis factor alpha, but not recombinant human interferon gamma, platelet-derived growth factor, or transforming growth factor beta caused selective eosinophilia of the pulmonary airways in the guinea pig. Unlike responses to latelet-activating factor, there was no attendant detectable airway hyperreactivity, but in common with responses to platelet-activating factor, eosinophilia of the airways was prevented by pretreatment with ketotifen or AH 21–132. Cytokines or lymphokines may contribute to pulmonary eosinophilia in diseases such as asthma.