Hyperoxia-Induced Protection against Rat's Renal Ischemic Damage: Relation to Oxygen Exposure Time

Background. Pre-exposure to hyperoxic gas (≥ 95%) has been shown to protect the heart and central nervous system from ischemia-reperfusion injury. In the present study, we investigated whether oxygen pretreatment induces delayed renal protection in rats. The possible role of some renal antioxidant agents was also investigated. Materials and methods. Adult male Wistar rats were kept in a hyperoxic (HO) (≥ 95% O₂) environment for 0.5 h, 1 h, 2 h, 3 h, 6 h, and 2 h/day for three consecutive days and 4 h/day for six consecutive days, and control group (IR) animals were kept in the cage with no HO, one day before subjecting their kidney to 40 minutes of ischemia and 24h of reperfusion. Renal function was assessed by comparing plasma creatinine (Cr), blood urea nitrogen (BUN), creatinine clearance (CLCr), and fractional excretion of sodium (FENa%). Histopathological injury score was also determined according to the Jablonski method. To examine the antioxidant system induction by hyperoxia, we measured renal catalase and superoxide dismutase activity, and renal glutathione and malondialdehyde content. Results. Our data demonstrated that only in 4 h/day HO for six consecutive days, the renal function tests (Cr, CLCr, BUN, and FENa%) and Jablonski histological injury were better than control group (p < 0.05). The beneficial effect of oxygen pretreatment in this group was associated with increased renal catalase activity compared with those obtained from control group (p < 0.05). Conclusion. The present study demonstrates that repeated exposure to hyperoxic (≥ 95% O₂) environment can reduce subsequent rat's renal ischemia-reperfusion damage. Induction of endogenous antioxidant system may partially explain this beneficial effect of hyperoxic preconditioning.     

Comparative assessment of the anti-Limnatis nilotica activities of Zingiber officinale methanolic extract with levamisole

The aim of this study was the evaluation of a methanolic extract of ginger compared with levamisole on Limnatis nilotica. In September 2010, 30 leeches from the southern area of Ilamprovince were prepared, and the effects of the methanolic extract of Zingiber officinale with levamisole were evaluated. The results of this study showed that methanolic extract of Z. officinale (600 mg/ml) could kill leeches at an average time of 33.3?±?11.4 min. The average time for death with levamisole (100 mg/ml) was 10.7?±?1.9 min. It was determined that both had an intensity of 4+, and distilled water used as negative control showed no effect on death and paralysis of L. nilotica. The present study has shown that Z. officinale has anti-leech effects and may be used in the treatment of infestation with L. nilotica in the future.     

Immunohistochemical study of expression of Caveolin-1 in canine malignant mammary tumour

Caveolin-1 (Cav-1) is thought to have an important impact on both signal transduction and the mediation of intracellular processes and may contribute to certain steps of carcinogenesis in various types of cancer. Cav-1 immunohistochemical expression was studied in 37 canine malignant mammary tumours to investigate the relationship of histopathological type and histopathologic grade with the expression of Cav-1. Cav-1 was expressed by epithelial cells in 33 of 37 (89.2 %) malignant mammary tumours. There was a significant relationship between epithelial expression of Cav-1 and histological grade of tumours (P?<?0.05); however, no significant relationship was observed between the expression of Cav-1 in myoepithelial and mesenchymal cells and histological grade (P?<?0.05). This study showed that Cav-1 can be used as a prognostic factor and its expression is associated with more malignant canine mammary tumours.