Exogenous succinate increases resistance of maize plants to copper stress

The effect of copper (Cu) excess (1.5, 4.7, 31, 78, 156 μM) and exogenously supplied succinate on plant growth, chlorophyll content, chlorophyll fluorescence, and isoenzym profiles of some antioxidant enzymes in maize plants was studied. Excessive Cu supply led to a reduction in the relative growth rate (RGR), tolerance index (TI), chlorophyll a and chlorophyll b contents, and the quantum yield of PSII electron transport in the light‐adapted state (ΦPSII). Copper treatment induced several changes in the anionic and cationic peroxidases (PODs), as well as superoxide dismutase (SOD) isoenzyme profiles. After 8 d of 78 μM–Cu treatment, two new anionic and two new cationic peroxidase isoenzymes in the roots were registered. Copper applied at concentrations above 31 μM resulted in higher levels of manganese superoxide dismutase (Mn‐SOD) in the roots and Cu,Zn‐superoxide dismutase (Cu,Zn‐SOD) in the leaves. However, the addition of Na‐succinate (200 μM) to the root medium prior to Cu treatment increased the capacity of the plants to partially overcome Cu toxicity.     

Alkaloid patterns in some varieties of Datura stramonium

A comparative GC-MS investigation of the alkaloid patterns of three varieties of Datura stramonium vars. stramonium, tatula and godronii, was carried out. Twenty-five tropane alkaloids were identified in the plant organs. Alkaloid patterns of the roots, leaves and seeds of the varieties grown at equal conditions in Bulgaria were very similar. In contrast, alkaloid pattern of D. stramonium var. stramonium, grown in Egypt, showed significant differences indicating that it is influenced more strongly by the environmental factors than genetic ones.     

Indirect immunofluorescent assay for antinuclear antibodies on McCoy-Plovdiv serum-free cell line substrate

Indirect immunofluorescent assay for antinuclear antibodies (IIFA-ANA) on HEp-2 cell substrate is a widely used test for diagnosis of connective tissue diseases. Recently, serum-free fibroblast cell line McCoy-Plovdiv has been developed to provide an alternative substrate. The aim of the present study was to evaluate the diagnostic performance of IIFA-ANA on McCoy-Plovdiv cell substrate for systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and compare it with that of the standard HEp-2 cell substrate. Sera from 72 patients with RA and 23 patients with SLE were tested with IIFA-ANA on both substrates. The control group consisted of 100 sera from healthy individuals. The agreement (Cohen's kappa) and the diagnostic performance (ROC analysis) of both methods were evaluated. IIFA-ANA on McCoy-Plovdiv cells proved to be comparable with the standard IIFA-ANA on HEp-2 cell substrate.