Unspecific redness of the eyelid--two malignant tumours.

Background: Chronic, non- or little pigmented reddish or brownish lesions on the lid margin and the surrounding skin are frequently underestimated and thus carry a clear risk of malignancy.

History And Signs: A 61-year-old lady was referred with a chronic, reddish lesion in the medial third of the left lower lid after a topical therapy over a period of 4 months had not improved the situation. She noticed the lesion for the first time 10 previously.

Contribution to the biological assessment of orthodontic acrylic materials. Measurement of their residual monomer output and cytotoxicity.

The acrylic materials used in orthodontics for the fabrication of removable appliances are subjected in the oral cavity to processes of change which influence their physical, mechanical and biological properties. It is therefore essential that every newly developed material must be judged in terms of its clinical value. In the present study, 2 orthodontic cold-cure acrylics, Orthocryl and Forestacryl, and 4 orthodontic photocure acrylics, Triad, Wil-O-Dont, Odontolux and Lux-A-Tech, were investigated and compared with 2 prosthetic acrylic materials: the cold-cure acrylic Palapress and the hot-cure acrylic Paladon.

Radiation-induced alterations of the proliferation dynamics of human skin fibroblasts after repeated irradiation in the subtherapeutic dose range.

Purpose: The aim of this study was to determine the effect of single and multiple irradiations on the differentiation and proliferation pattern of the stem cell system of human fibroblasts.

Methods: The pattern of differentiation of fibroblast cultures was analyzed by morphological criteria using colony forming assays. Proliferation rates were assessed by cell counting and measuring the incorporation of BrdU.

Mutant analysis suggests that cyclic GMP mediates the cyclic AMP-induced Ca2+ uptake in Dictyostelium.

Previous work has shown that streamer F (stmF) mutants of Dictyostelium discoideum exhibit prolonged chemotactic elongation in aggregation fields. The mutants carry an altered structural gene for cyclic GMP phosphodiesterase resulting in low activities of this enzyme. Chemotactic stimulation by cyclic AMP causes a rapid transient increase in the cyclic GMP concentration followed by association of myosin heavy chains with the cytoskeleton.

A high-affinity plasma membrane Ca2+-ATPase in Dictyostelium discoideum: its relation to cAMP-induced Ca2+ fluxes.

Chemotactic stimulation of Dictyostelium discoideum induces an uptake of Ca2+ by the cells followed by a release of Ca2+. In this study we investigated the mechanism of Ca2+ release and found that it was inhibited by La3+, Cd2+ and azide. Ca2+ release occurred in the absence of external Na+, indicating that an Na+/Ca2+ exchange was not involved.