Exogenous testosterone differentially affects myelination and neurone soma sizes in the brain of canaries.

We assessed the temporal and functional relationship of myelin maturation and of neuronal development in the telencephalic song motor centres of the canary at different developmental stages. Brain differentiation was modulated by exogenous testosterone, its effects on song quality were also monitored. Myelin maturation was studied by using computer aided analysis of silver impregnated brain sections, whereas the differentiation of neurones was determined by measuring neuronal soma sizes.

Antioestrogen inhibits myelination in brains of juvenile Zebra finches.

The effects of the antioestrogen Keoxifene on the ontogenetic process of myelination, on the differentiation of neurones of telencephalic song motor centres, on cerebellar structures and on behaviour were studied in male Zebra finches. Brain differentiation was studied by using computer aided analysis of silver impregnated brain sections and by measuring soma sizes of neurones after Nissl staining. An antioestrogen induced inhibition of myelination could be detected in the song motor centre robust nucleus of the archistriatum (RA) and in the cerebellum, whereas the region magnocellular nucleus of the anterior neostriatum (MAN) showed no difference between treated birds and controls.

[Use of computer-assisted image analysis for the detection of immunohistochemical receptor status in breast cancer. Immunohistochemical densitometry receptor analysis--IRDA].

A method for the evaluation of the immunohistochemical staining score of steroid receptors in breast cancer using computer-based image analysis is presented. The optical density of tumour cell nuclei was measured using kryostat sections and, using a control section as reference, an objective threshold for specific staining was defined. In intensively stained sections, a good correlation with visual scoring was achieved, but in 9 out of 16 sections, which were regarded as receptor-negative by visual scoring, a specific receptor-positive staining was demonstrated by image analysis.

An electronic primer in dermatopathology.

We present an electronic primer in dermatopathology based on a full-text retrieval system which contains all the features of traditional handbooks of dermatopathology. The system including high-resolution black and white pictures with coloured overlays runs on every personal computer with VGA card and needs no additional software and hardware equipment. The representation of pictures is improved by using high-resolution VGA cards.

Application of testosterone accelerates oligodendrocyte maturation in brains of zebra finches.

The effects of exogenously applied hormones on glial cell maturation of telencephalic song motor centers, midbrain and cerebellar structures was studied in juvenile male zebra finches. Testosterone was administered and the development of oligodendrocytes was studied using immunochemistry and computer aided image analysis on silver impregnated brain sections. A testosterone induced acceleration of oligodendrocyte maturation could be detected in several brain areas by using the monoclonal antibody O 10 recognizing an oligodendrocyte-specific cell surface antigen and by the silver impregnation for myelin.