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Showing papers on "Animal mortality published in 1987"


Journal Article
TL;DR: The hypothesis that chelates of iron are important in the cytotoxicity of reactive oxygen species, possibly through initiating the cleavage of peroxyl bonds is tested and a possible causal role for Fenton chemistry and lipid peroxidation in diquat-generated, reactive oxygen-mediated hepatic injury in vivo is suggested.
Abstract: The hepatic necrosis produced in Fischer-344 rats by diquat appears to be mediated by redox cycling of diquat with generation of reactive oxygen species. We have now tested the hypothesis that chelates of iron are important in the cytotoxicity of reactive oxygen species, possibly through initiating the cleavage of peroxyl bonds. Pretreatment with the iron chelator desferrioxamine, 0.24 mmol/kg intraperitoneally, attenuated the hepatic damage produced by diquat. No additional protection was provided by a second dose of desferrioxamine 2 hr after diquat or by administration of the iron chelator by a different route of administration (subcutaneously). Ferrous sulfate (0.36 mmol/kg, intraperitoneally) alone produced no hepatic injury, but when given 15 min before diquat, it potentiated hepatic injury and animal mortality. In contrast, biliary excretion of glutathione disulfide in response to administration of diquat was neither potentiated by pretreatment with FeSO4 nor diminished by pretreatment with desferrioxamine. The marked changes in hepatic injury produced by these pretreatments, without changes in glutathione disulfide production, indicate that shifts in thiol/disulfide equilibria are not likely to be initiating events in the pathogenesis of diquat-induced hepatic necrosis. Administration of a hepatotoxic dose of diquat quickly produced 5-fold stimulation of ethane and pentane expiration rates with return to control rates by 3 hr. Desferrioxamine markedly inhibited, and iron potentiated, hydrocarbon expiration in response to diquat. The parallel changes in diquat hepatic injury and ethane and pentane expiration rates in response to manipulation of iron availability suggest a possible causal role for Fenton chemistry and lipid peroxidation in diquat-generated, reactive oxygen-mediated hepatic injury in vivo.

59 citations


Journal Article
01 Aug 1987-Surgery
TL;DR: The data suggest that the influence of nutritional repletion on the tumor-bearing host varies specifically with the presence of an antitumor immune response.

11 citations


Journal ArticleDOI
TL;DR: Glucan, a derivative of the cell wall of Saccharomyces cerevisiae and a potent immunostimulant, was used in combination with cyclophosphamide for treatment of implanted murine transitional cell carcinoma.

8 citations


01 Jan 1987
TL;DR: The Genus Baccharis, as represented in certain communities of the Frovince of Buenos Aires, shows five species a done variety, all toxic for cattle, which can be correctly identified, whereas the variety was only determined to its Ilearest specific level.
Abstract: The Genus Baccharis, as represented in certain communities of the Frovince of Buenos Aires, shows five species a done variety, all higWy toxic for cattle. Tberefore, an approach to the systematics of these taxa through non·conventional morphological characters, such as leaf epidermis, was considered to be' pertinent if diagnoses on causes of animal mortality \Vere to be performed by means of feces ami stornach contents. Accordingly, this approach has led to formlllate cell types based on contollr, size and length/width ratios of ieaf (epidermic) cells, plus hairs and stomata. The five species couJd thus be correctly identified, whereas the variety was only determined to its Ilearest specific level.

5 citations