Johann Hobson

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BACKGROUND Brain 5-hydroxytryptamine (5-HT) function is implicated in the pathophysiology of schizophrenia and the action of new generation antipsychotic drugs. By the method of acute tryptophan depletion (ATD) 5-HT can be selectively manipulated. The aim of this study was to examine the effects of ATD on symptoms, mood and cognition in schizophrenic(More)
Cigarette smoke is believed to increase the pulmonary retention of many different types of mineral dusts, but the mechanisms of this process are unclear. We have previously shown, using a tracheal organ culture system, that exposure to cigarette smoke directly increases the uptake of asbestos fibers by tracheal epithelial cells, and that this process is(More)
BACKGROUND Most patients with psoriasis have limited disease which can be managed effectively in primary care. There is a marked variation in the frequency of referrals between practices reflecting, in part, inadequate training of general practitioners (GPs) in the management of psoriasis. OBJECTIVES To assess the effectiveness of guidelines and training(More)
Cigarette smoke is known to contain many types of free radicals, and solutions of smoke tar have been shown to liberate hydrogen peroxide as well as superoxide radical. To further investigate the relationship of smoke exposure and generation of active oxygen species, the authors exposed rat tracheal explants to varying amounts of smoke for 10 minutes in a(More)
To examine the mechanism whereby asbestos fibers penetrate tracheal epithelial cells, we exposed rat tracheal explants to amosite asbestos alone, or with varying concentrations of substances that scavenge active oxygen species (catalase and superoxide dismutase) or prevent formation of active oxygen species (deferoxamine). All three agents decreased(More)
We have identified GR138950, a potent antagonist of the angiotensin II receptor with high oral bioavailability, as our second drug candidate to GR117289. Using GR117289, a compound with moderate bioavailability (20%) in man as a lead, we pursued a strategy aimed at enhancing bioavailability. The strategy was based on SAR established around the diacid(More)
to determine the effect of smoking cessation on the number and type of inflammatory cells in the walls of the small airways, we examined the lungs of 13 lifetime nonsmokers, 25 patients who had stopped smoking for at least 6 months, and 49 current smokers. We found that, compared to nonsmokers, both ex-smokers and current smokers had significantly increased(More)
We examined the structure of the membranous and respiratory bronchioles of lungs resected from nonsmokers and compared these to those obtained from current and exsmokers. The structure of both types of airways was altered by cigarette smoking, and these pathologic changes were accompanied by differences in pulmonary function. The walls of membranous(More)
This study was designed to investigate the relationship between the cellular components of lung lavage fluid and the presence of airways disease and emphysema in resected lung specimens, primarily from current and ex-smokers. Since standard bronchopulmonary lavage cannot be performed on these specimens, an intrapulmonary lavage technique was developed and(More)
This study compares the inflammatory cell types in the alveolar airspace, peripheral airways, and bronchoalveolar lavage fluid of 65 human lung specimens removed surgically. The data show that the cellular population in the airway tissue is composed of approximately 2–4% neutrophils, and 96–98% mononuclear inflammatory cells. This contrasts with the airway(More)