In recent years, genetically altered mice, either overexpressing or deficient in specific gene products, have come to play a vital role in experimental studies designed to probe the molecular pathophysiology of ischemic brain injury. More than 100 such studies have been reported to date, and notable successes have been achieved in elucidating the roles of the neuronal,1,2 endothelial,3 and indu...

Glutathione peroxidase (GPx) is a family of antioxidant enzymes that reduce reactive oxygen species (ROS), thereby constituting a primary defence system against oxidative stress. Of the five characterised isoforms of GPx found in mammals, GPx1 is the predominant intracellular form and GPx3 is the predominant form found in the extracellular space1. Experimental studies have demonstrated that def...

Reactive oxygen species (ROS) have been implicated in the pathogenesis of many clinical disorders such as adult respiratory distress syndrome, ischemia-reperfusion injury, atherosclerosis, neurodegenerative diseases, and cancer. Genetically engineered animal models have been used as a tool for understanding the function of various antioxidant enzymes in cellular defense mechanisms against vario...

Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO(2)]) or chronic elevated ozone concentration ([O(3)]; 90 ppb), and then exposed to an acute O(3) stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxida...

Abstract Metal pollution represents a serious issue for sustainable agronomy and food safety. Activation of plants’ protective mechanisms has been shown to depend on the extent soil contamination with metal, but reports dose-dependent responses (especially extreme concentrations) are rather rare. In this research we exposed soybean ( Glycine max L.) roots at very early stage scale cadmium conce...

Polyphenoloxidase was purified from chloroplasts of broad bean leaves (Vicia faba L.) to apparent homogeneity. The enzyme was composed of two proteins with an apparent mass of 65 and 68 kilodaltons after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isolated enzyme contained covalently attached carbohydrates and bound concanavalin A, Phaseolus vulgaris erythroagglutinin, and Ri...

Objective(s) Phosphatidate phosphohydrolase (PAP) catalyzes the dephosphorylation of phosphatidic acid to yield Pi and  diacylglycerol. Two different forms of PAP in rat hepatocyte have been reported. PAP1 is located in cytosolic and microsomal fractions and participates in the synthesis of triacylglycerols, phosphatidylcholine, and phosphatidylethanolamine, whereas the other form of phosphati...

inducible nitric oxide synthase (inos) gene expresses a calcium calmudolin-independent enzyme which can catalyse no production from l-arginine. the induction of inos activity has been demonstrated in a wide variety of cell types under stimulation with cytokines and lipopoly saccharide (lps). previous studies indicated that all nitric oxide synthases (nos) activated in human umbilical vein endot...