Gill reaction to pollutants from the Tamis River in three freshwater fish species, Esox lucius L. 1758, Sander lucioperca (L. 1758) and Silurus glanis L. 1758: a comparative study.

The study evaluated the effects of waterborne pollutants from the Tamis River on gill histology and possible differences in gill reaction patterns between three freshwater fish species, pike Esox lucius L. 1758, pike-perch Sander lucioperca (L. 1758) and wels catfish Silurus glanis L. 1758 from the Tamis River. Gills from analysed fish species showed moderate to intense histopathological alterations. The most frequent progressive alteration was hyperplasia of epithelium, whereas the most frequent regressive alteration was epithelial lifting. Circulatory disturbances were most often manifested in the form of hyperaemia. During comparative analysis, differences in gill indices, reaction and alteration indices, as well as in gill and filament prevalence between analysed species, were observed. Although all analysed fish species did show both progressive and regressive alterations, there was a significant difference in the level of expression of these reaction patterns. Gill index obtained for pike clearly stands out as the lowest. Wels catfish showed the highest progressive reaction index, significantly higher in comparison with the other two species (P < 0.05), while pike-perch showed the highest regressive reaction index, also significantly higher in comparison with the other species (P < 0.001). These results may implicate species-specific gill reactions and thus present a useful tool for better understanding toxic mechanisms of various pollutants.

[Quantitative analysis of the electroencephalogram in healthy school-age children]. / Kvantitativna analiza elektroencefalograma zdrave dece osnovnoskolskog uzrasta.

Topography of EEG power spectra in a sample of 72 healthy children aged 7 to 15 years, was studied. The children were volunteers, satisfying general criteria of normality. The EEGs were recorded at 16 scalp locations in subjects with closed eyes and measured in monopolar recording on a split screen of a system for video EEG monitoring. Each signal of EEG channels was digitized with 12-bit resolution and processed by a PC computer. The raw EEG was transformed by fi-time domain into the frequency domain using the fast Fourier transforms. In-transformed absolute power and relative power were used as parameters. In the present study it was shown that total power was mainly influenced by alpha power. Maximal delta activity exhibited in anterior and posterior derivations, while minimal activity was measured in central and mid-temporal locations. Theta power was mostly pronounced in posterior derivations. Beta-1 band activity was maximal in posterior and minimal in anterior derivations. Significant power decrease in beta-2 power was also characteristic of posterior locations. Diagrammatic presentation of In-transformed absolute power over brain regions (frontal, central, midparieto-occipital and temporal) gave a summary of distributions shown earlier. Most of the relative powers were found in alpha band, especially in parieto-occipital region.

[Bovine spongiform encephalopathy: a review]. / Die Bovine Spongiforme Enzephalopathie: Eine Ubersicht.

Transmissible Spongiform Encephalopathies are a group of chronic, always fatal diseases affecting the central nervous system of humans and animals. They occur in all species and are probably caused by agents called prions. In this minireview, a first part provides an overview of the various disease forms, a second part is devoted to the molecular biology of transmissible spongiform encephalopathies, and a last part deals with the specific problems of the Bovine Spongiform Encephalopathy.