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Response of lung enzyme activities in rabbits following short-term exposure to n-hexane: correlation between morphological and biochemical changes
No full textThe activity of lactate dehydrogenase, beta-glucuronidase, glucose-6-phosphate dehydrogenase, acid and alkaline phosphatase was studied in lung homogenate from New Zealand rabbits exposed to 3000 p.p.m. of n-hexane 8 h per day for 8 days of filtered air. In hydrocarbon-treated animals all enzymes examined, except alkaline phosphatase, were markedly increased. The biochemical changes correlated well with the morphological changes and the results of cytological evaluation of bronchopulmonary lavage. It is suggested that high values in lung lysosomal enzymes from treated rabbits reflect the acute inflammation whilst the increase in lung glucose-6-phosphate dehydrogenase may depend upon reparative process subsequent to n-hexane-induced lung damage
Pulmonary changes induced in rabbits by long-term exposure to n-hexane
No full textNew Zealand male rabbits were exposed in an inhalation chamber to 3,000 ppm of n-hexane 8 h/day, 5 days/week for 24 weeks, resulting in a total of 120 exposures. After a further 120 days in clean air, morphologic examination of lungs by light and transmission electron microscopy (TEM) revealed three important exposure-related lesions. These consisted of air space enlargement centered on respiratory bronchioles and alveolar ducts (centriacinar emphysema), scattered foci of pulmonary fibrosis, and papillary tumors of non-ciliated bronchiolar epithelial cells. At TEM examination these tumors were rather homogeneous and were found to consist of cells showing both small and large electron dense ovoid granules in their cytoplasmic matrix, a feature that has been described for Clara cells. The implications of these findings are discussed
Fatal Ketamine abuse: a report of a case and analytical determination by gas liquid chromatography/mass spectometry
No full textBinding features of diacetylmorphine (heroin) in whole blood and in blood fractions
No full textBinding features of heroin in whole blood and in blood fractions were delineated by measuring the selective spin-lattice relaxation rates of heroin protons in physiologic conditions. Interaction with some receptor located in the whole human blood or in the human plasma was detected and the apparent binding constant calculated (K = 39 mol-1 dm3). Inferences about molecular dynamics of the bound heroin could be also gained
Conformational and dynamic features of cocaine in DMSO-d6 solution
No full text13C spin-lattice relaxation rates, 13C {1H} NOESs, 1H spin-spin relaxation rates and1H two-dimensional magnetization transfer spectroscopy were used for delineating conformationalfeaturesofcocaine in DMSO-d6 solution. Two main conformations differing in the orientation of the plane made by the benzoxy substituent with respect to the piperidine ring principal axis were observed. Relatively slow interconversions of the piperidine ring were delineated together with the main motional featuresof the whole molecule
Distribution of hyoscyamine and scopolamine in Datura stramonium
No full textThe production of hyoscyamine and scopolamine in Datura stramonium has been investigated in the different plant parts, at different stages of their life cycle. Maximum contents were found in the stems and leaves of young plants, hyoscyamine being always the predominant component. (C) 2001 Elsevier Science B.V. All rights reserved
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