Alveoles

RESPIRATORY SENSITIZER (asthmagen) A substance which can cause an individual s respiratory system to develop a condition which makes it over-react if the substance is inhaled again. Such an individual is sensitized over-reaction is then likely to occur at concentrations of the substance which have no effect on unsensitized persons and lead to characteristic symptoms, e.g. rhinitis (a runny nose), conjunctivitis or in severe cases asthma or alveolitis. 

In type III or immunocomplex-mediated allergy, IgG antibodies form complexes with antigen. At low exposures, the body is able to remove diese complexes, but if there is a severe exposure, immunocomplexes release a variety of proinflammatory cytokines. The involvement of this mechanism is clearest in serum sickness. This mechanism is also considered to be most important in the development of extrinsic allergic alveolitis (hypersensitivity pneumonitis, especially... 

Allergic alveolitis An allergic response to inhalation of organic particles that involves inflammation of the small terminal branches of the bronchioles. Symptoms include coughing, increased production of mucus, fever, fatigue, and muscle aches. 

RESPIRATORY SENSITIZER A substance that may cause sensitization on inhalation, causing, e.g., asthma, rhinitis or extrinsic allergic alveolitis. 

In a percussive brain injury model in cats, N-acetylcysteine (NAG) preserved normal hyperventilation when administered either prior to or 30 min post-insult (Ellis etal., 1991), NAG was also found to be active in a model of acute immunological alveolitis in the rat in... 

FIGURE 1-6 A portion of a Golgi apparatus. The smooth-mem-braned cisternae appear beaded. The many circular profiles represent tangentially sectioned fenestrations and alveolate vesicles (primary lysosomes). Two of the latter can be seen budding from Golgi saccules (arrows). Mitochondria and a dense body (secondary lysosomes) are also present. x60,000. 

A number of studies of the toxicity of zinc oxide/hexachloroethane smoke have been conducted (Brown et al. 1990 Karlsson et al. 1986 Marrs et al. 1983). These studies demonstrate that smoke exposure results in pulmonary inflammation and irritation. When male Porton Wistar rats were exposed to hexachloroethane/zinc oxide smoke for 60 minutes, the lungs showed pulmonary edema, alveolitis, and areas of macrophage infiltration 3 days later. At 14 days, there was interstitial fibrosis and macrophage infiltration. At 28 days, increased fibrosis and macrophage infiltration were noted. However, these same symptoms occurred when the animals inhaled zinc chloride there was no apparent synergism between the zinc chloride and residual hexachloroethane (Brown et al. 1990 Richard et al. 1989). This is consistent with the fact that smoke contains little hexachloroethane and the observation that acute exposure to 260 ppm hexachloroethane had no effects on the lungs of rats (Weeks et al. 1979). 

PULM pulmonary region (alveolated airways and alveoli). 

Continued lung injury from inhalation of particulates, whatever their source, size, or composition, produces inflammation (alveolitis, bronchitis), and perhaps eventually fibrosis, a pathological reaction that distorts the architecture of the airways (Lippman et al., 1971). Lung function is compro-... 

In guinea pigs 120mg zinc/m as zinc chloride 1 hour/day 5 days/week for up to 3 weeks was lethal focal alveolitis, consolidation, emphysema, infiltration with macrophages, and fibrosis were observed at necropsy. Mice and rats exposed to 122 mg zinc/m as zinc chloride for 1 hour/day, 5 days/week, survived 20 weeks of exposure but showed increased macrophages in lungs when euthanized 13 months after exposure. ... 

Hepatotoxicity Penicillamine has been associated with a mild elevation of hepatic enzymes that usually returns to normal even with continuation of the drug. Autoimmune syndromes Autoimmune syndromes that may be caused by penicillamine include polymyositis, diffuse alveolitis and dermatomyositis, Goodpasture s syndrome, myasthenic syndrome, pemphigus, and obliterative bronchiolitis. 

Deaths Deaths associated with the administration of sulfasalazine have been reported from hypersensitivity reactions, agranulocytosis, aplastic anemia, other blood dyscrasias, renal and liver damage, irreversible neuromuscular and CNS changes, and fibrosing alveolitis. If toxic or hypersensitivity reactions occur, discontinue sulfasalazine immediately. 

In a study of the time course of nickel-induced respiratory lesions, rats were exposed at 0, 0.22, or 0.95 mg nickel/m as nickel subsulfide 6 hours/day for up to 22 days (Benson et al. 1995b). Inflammatory lung lesions peaked at day 4 of exposure at the high concentration. Alveolitis was noted at the low concentration in all six exposed rats after 7 days of exposure (rats exposed to the low concentration were not examined at earlier time points). Following 6 months of exposure (6 hours/day, 5 days/week), alveolitis of moderate severity was observed in rats exposed to nickel oxide at 1.96 mg nickel/m and mild alveolitis was observed in rats exposed to nickel sulfate at 0.11 mg nickel/m (Benson et al. 1995a). In mice, interstitial pneumonia was observed at 0.98 mg nickel/m and 0.22 mg... 

Serious, potentially fatal pulmonary toxicity (alveolitis, pulmonary fibrosis, pneumonitis, acute respiratory distress syndrome) may begin with progressive dyspnea and cough with crackles, decreased breath sounds, pleurisy, CH F, or hepatotoxicity. 

Pulmonary fibrosis, interstitial pneumonitis, fibrosing alveolitis, pulmonary edema, and pneumonitis have been reported. 

Malo JL, Ouimet G, Cartier A, et al. 1983. Combined alveolitis and asthma due to hexamethylene diisocyanate, with demonstration of crossed respiratory and immunologic reactivities to diphenylmethane diisocyanate. J Allergy Clin Immunol 72(4) 413-419. 

Possible Roles of insoluble Carbohydrates in Texture Development. Based on data obtained frcm soy isolate-soy hull blend texturization experiments, insoluble carbohydrates and crude fiber play an important role in modulating the morphology of final texturized products (Figures 11-14). Insoluble carbohydrates, because of their plastic response to deformation, control the type of alveolation developed during processing. 

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