Archive for the 'Human Airway Disease' Category

21 Nov

Utility of Animal Models in the Study of Human Airway Disease: Comparisons Between Animal Models and Human Disease (Part 2)

The morphologic changes in human bronchial asthma typically consist of submucosal gland hypertrophy and hyperplasia, loss of cilia, increased amounts of mucus in airway lumina, varying degrees of subepithelial vascular congestion and edema, and airway smooth muscle hypertrophy. In addition, infiltration of the airway wall with leukocytes is frequently present. Most of these lesions have […]

20 Nov

Utility of Animal Models in the Study of Human Airway Disease: Comparisons Between Animal Models and Human Disease (Part 1)

In evaluating the merit of using animals as models of bronchial asthma, several questions arise. Are the functional characteristics of the human disease present in animals? Can the typical histologic lesions of asthma be reproduced in animals? Does the similarity in the physiologic endpoints between humans and animals imply similar underlying mechanisms?

19 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 8)

Airway Microcirculation In patients with severe bronchial asthma, the airway mucosa is morphologically characterized by microvas-cular congestion and edema of the airway wall. These findings suggest that the airway circulation participates in the asthma-associated airway inflammation. Since the airway circulation is difficult to study in humans because of the requirement of invasive techniques, animals have […]

18 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 7)

Ciliary dysfunction is another possible cause of impaired mucociliary interaction. In contrast to epithelial secretion, ciliary activity has been shown to respond inconsistently to inflammatory stimuli. While serum protein, eosinophil major basic protein, and adenosine have been found to inhibit ciliary activity in rabbits, guinea pigs and lower animals, the leukotrienes C4, D4 and the […]

17 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 6)

These examples demonstrate that the different animal models of airway smooth muscle hyperresponsiveness involve different pathogenetic pathways. The animal studies therefore cannot answer the question of which of these mechanisms are also operative in humans with airway hyperresponsiveness. buy diabetes drugs Airway Epithelium In patients with bronchial asthma, the airway epithelium secretes liquids at an […]

16 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 5)

Thus, the influx of inflammatory cells into the airway seems to play a critical role in nonimmunologically-induced airway hyperresponsiveness in the dog model but not in the guinea pig model, and different chemical mediators seem to be involved in the development of airway hyperresponsiveness in the two species. Possibly, the activation of resident leukocytes in […]

15 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 4)

A role for thromboxane in immunologically induced airway hyperresponsiveness has also been shown in mongrel dogs. Further studies in dogs and sheep have raised the possibility that the antigen-induced release of anaphylactic mediators (eg, LTB4, PAF) may be a critical step in the development of airway hyperresponsiveness. Whether or not the subsequent influx of granulocytes […]

14 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 3)

In allergic mongrel dogs, a single inhalation challenge with specific antigen has been shown to increase cholinergic bronchial responsiveness after six hours; the hyperresponsiveness lasted up to 96 hours after challenge. Becker et al found in mongrel dogs neonatally sensitized with ragweed antigen, a progressive increase in airway responsiveness to inhaled acetylcholine during a 15-month […]

13 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 2)

In some offsprings of Basenji dogs crossed with Greyhounds, a strong sensitivity to As-caris suum antigen and marked in vivo airway responsiveness to spasmogens and irritants has been observed. The specific (antigen) and nonspecific responsiveness was greater in these animals than in Basenji dogs, Greyhounds, or mongrel dogs. The mechanisms of hyperresponsiveness in Basenji-Grey-hounds are […]

12 Nov

Utility of Animal Models in the Study of Human Airway Disease: Experimental Models (Part 1)

The popular models of human airway hyperresponsiveness include different rodents, the dog, the sheep, the pony, and subhuman primates. Previous reviews have either stressed the advantages and disadvantages of the different species as compared to each other or┬áto humans or classified the animal models according to the cause of airway hyperresponsiveness. These categories are genetically […]

© 2017 - Men’s Health Info Blog