Ryszard T Dworski

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Asthma is a chronic inflammatory disease of the respiratory tract of unknown aetiology. In severe asthma airway diathesis is profound, and thus apparent. Recently, however, evidence has indicated that specific inflammatory abnormalities exist even in the airways of subjects with mild disease. As inflammation is often associated with an increased generation(More)
Eosinophilic bronchitis is a common cause of chronic cough, which like asthma is characterized by sputum eosinophilia, but in contrast to asthma there is no variable airflow obstruction or airway hyperresponsiveness. Our hypothesis was that the differences in airway pathophysiology maybe due to less active airway inflammation in eosinophilic bronchitis,(More)
BACKGROUND Asthma is a heterogeneous inflammatory airway disorder that involves eosinophilic and noneosinophilic phenotypes. Unlike in healthy lungs, eosinophils are often present in atopic asthmatic airways, although a subpopulation of asthmatic subjects predominantly experience neutrophilic inflammation. Recently, it has been demonstrated that eosinophils(More)
BACKGROUND Systemic blockade of tissue factor (TF) attenuates acute lung injury (ALI) in animal models of sepsis but the effects of global TF deficiency are unknown. We used mice with complete knockout of mouse TF and low levels (∼1%) of human TF (LTF mice) to test the hypothesis that global TF deficiency attenuates lung inflammation in direct lung injury.(More)
Further definition of the role of leukotrienes (LT) and prostaglandins (PG) in asthma would be helped by a noninvasive method for assessing airway production. The supernatant from sputum induced with hypertonic saline and dispersed using dithiotrietol has been successfully used to measure other molecular markers of airway inflammation and might be a useful(More)
Prostaglandin E2 (PGE2), a potent mediator of inflammation released in large amounts by endotoxin-stimulated alveolar macrophages (AM), has been shown to inhibit leukotriene B4 (LTB4) release by activated neutrophils. We investigated the hypothesis that LTB4 synthesis by AM can be regulated by PGE2 and performed experiments to determine the biochemical site(More)
Treatment of inflammatory diseases of asthmatics can be a serious problem since some patients show intolerance to aspirin and other non-steroidal, anti-inflammatory drugs that are cyclooxygenase inhibitors. Salicylates were believed to be well tolerated, but recent reports have demonstrated that diflunisal and salicylsalicylic acid can precipitate asthma(More)
The isoprostanes (IsoPs) are a series of novel prostaglandin (PG)-like compounds generated from the free radical-catalyzed peroxidation of arachidonic acid. The first series of IsoPs characterized contained F-type prostane rings analogous to PGF2alpha. One F-ring IsoP, 15-F2t-IsoP (8-iso-PGF2alpha) has been shown to be formed in abundance in vivo and to(More)
The mechanism of steroid action in asthma is unknown. Because steroids have effects in vitro on eicosanoid synthesis, we determined the effect of oral prednisone for 6 to 9 days on eicosanoid levels in bronchoalveolar lavage (BAL) fluid of 14 atopic asthmatic volunteers at baseline and after allergen instillation. We also determined the effect of prednisone(More)
Asthma is a chronic inflammatory disease of the airways which may involve an oxidant injury to the lung. Assessment of oxidant stress is difficult in vivo, but measurement of F2-isoprostanes (F2-IsoPs), free radical-catalysed products of arachidonic acid, appears to offer a reliable approach for quantitative measurement of oxidative stress status in vivo.(More)