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26 Pags.- 6 Figs. The definitive version is available at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1399-3054 ; The antioxidant composition and relative water stress tolerance of nodulated alfalfa plants (Medicago sativa L. x Sinorhizobium meliloti 102F78) of the elite genotype N4 and three derived transgenic lines have been studied in detail. These transgenic lines overproduced, respectively, Mn-containing superoxide dismutase (SOD) in the mitochondria of leaves and nodules, MnSOD in the chloroplasts, and FeSOD in the chloroplasts. In general for all lines, water stress caused moderate decreases in MnSOD and FeSOD activities in both leaves and nodules, but had distinct tissue-dependent effects on the activities of the peroxide-scavenging enzymes. During water stress, with a few exceptions, ascorbate peroxidase and catalase activities increased moderately in leaves but decreased in nodules. At mild water stress, transgenic lines showed, on average, 20% higher photosynthetic activity than the parental line, which suggests a superior tolerance of transgenic plants under these conditions. However, the untransformed and the transgenic plants performed similarly during moderate and severe water stress and recovery with respect to important markers of metabolic activity and of oxidative stress in leaves and nodules. We conclude that the base genotype used for transformation and the background SOD isozymic composition may have a profound effect on the relative tolerance of the transgenic lines to abiotic stress. ; M.C.R. was the recipient of a pre-doctoral fellowship from the Ministry of Education and Culture. This work was supported by grant 2FD97-1101 from the Comisión Interministerial de Ciencia y Tecnología and the European Union and by grants PB98-0522 and PB98-0545 from the Dirección General de Enseñanza Superior e Investigación Científica. The Institute of Grassland and Environmental Research is grant aided by the Biotechnology and Biological Sciences Research Council. ; Peer Reviewed

This study was carried out at the Tissue Culture Laboratory, which belongs to the General Commission of Biotechnology, in order to evaluate the influence of NaCl-induced salinity stress on some oxidative parameters (MDA and H2O2) and antioxidant enzymes (CAT, APX, and SOD) in eight durum wheat genotypes (Doma1, Bouhoth11, Cham3, Bezater, Cham5, Aghamatales, Icaverve, and Icamber) in vitro, to determine the most salinity tolerant genotypes. Salinity stress was applied by adding different levels of NaCl to the growing medium (0, 50, 100, and 150 mM). The experiment was laid according to a complete randomized design (CRD) with sixteen replicates. Increasing salinity level caused an increase in both the Hydrogen peroxide (H2O2), malondialdehyde (MDA) and the activity of the investigated antioxidant enzymes (SOD، APX، CAT) compared with the control. The leaf content of both H2O2 and MDA was significantly higher in the genotype Icaverve at the salinity level of 150 mM NaCl (45.67 and 130.74 µmol g-1 fresh wt. respectively), while the activity of the enzymes SOD, APX and CAT were significantly higher in the two durum wheat genotypes, Bouhoth11 and Doma1 at the highest salinity level (150 mM NaCl). Antioxidant enzymes play a pivotal role in the defense mechanisms in the durum wheat under salinity stress conditions, and the in vitro screening tool can be effectively used to assess the genetic variability for salinity tolerance in the durum wheat crop.

Abstract
Background Complex underlying mechanisms consisting of cytotoxic, excitotoxic, and inflammatory effects of intraparenchymal hemorrhage (ICH) are responsible for the highly detrimental effects on brain tissue. Oxidative stress also plays a significant role in brain damage after ICH; however, it is less important than other factors. In this study, we aimed to evaluate the oxidative stress parameters malondialdehyde (MDA) and antioxidant-reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CT) activities in operated and nonoperated patients with spontaneous ICH.
Methods One hundred patients with spontaneous ICH and 100 healthy controls were included in this study. Within the indication, 50 of the 100 patients underwent decompressive surgery. MDA, GSH, SOD, and CT activities were measured in the serum obtained from the patients.
Results SOD and CT levels were lower in the nonoperated group than in the operated and control groups. GSH was similar in the operated and nonoperated groups, but it was lower in the control group. However, MDA was higher in those who did not undergo surgery than in the other groups.
Conclusions In our study, MDA, an indicator of oxidative stress, was found to be lower, and CT and SOD activities were found to be higher in ICH patients who underwent decompression than in those who did not. This is the first study to present the correlations of MDA, SOD, CT, and GSH in operated and nonoperated patients with spontaneous ICH.