West & West syndrome--a historical sketch about the eponymous doctor, his work and his family.

The British surgeon William James West has not left a tremendous literary or scientific work as many of his contemporaries did. For this reason only a little has been known about him and the fate of his family for decades, even though the eponym was created in the 1960s. Only in 1990 was a first biography published and later on supplemented.

Reactivation of a cell-free model from Physarum polycephalum: studies on cryosections indicate an inhibitory effect of Ca++ on cytoplasmic actomyosin contraction.

Cell-free models should offer "in situ conditions" to study the physiology of cytoplasmic actomyosin in its natural environment, while, if possible, still associated with its regulatory control proteins and other cytoplasmic components. Detergents and glycerol as the usual media to permeabilize the plasmalemma and to extract a portion of the cytoplasmic components, are accompanied by several disadvantages. We investigated a cell-free model consisting of cryosections of plasmodial strands that were previously enriched with "stress fibrils" and fluorescently labelled with phallotoxins and that contain the non-denatured structures that are to be reactivated in situ.

Enrichment of fibrillar cytoplasmic actomyosin in protoplasmic strands of Physarum polycephalum for the production of cell-free models.

The treatment of isolated protoplasmic strands of Physarum polycephalum with 2.5% ethanol in a physiological salt solution under isometric conditions induces the formation of a large amount of mostly longitudinally organized actomyosin fibrils in the endoplasmic channel, a region normally free of actomyosin fibrils. The quantity of fibrillogenesis as well as the concomitant force output during the induced contractures are dependent on the Ca++-content and the temperature of the test solution.

Reactivation of NBD-phallacidin-labelled actomyosin fibrils in cryosections of Physarum polycephalum: a new cell-free model.

Application of ATP to cryosections of plasmodial strands from Physarum polycephalum leads to an isotonic contraction of the cytoplasmic actomyosin fibrils: when the fibrils are labelled with NBD-phallacidin, their contraction can be observed in the fluorescence microscope. While performing contraction, the fibrils separate into many small units and the formerly continuous fibrils exhibit the appearance of beaded chains. The possibility of visualizing directly the contraction of cytoplasmic actomyosin fibrils in the fluorescence microscope represents a favourable condition for the study of their physiological contraction mechanism, because this new and convenient cell-free model offers in situ contractile structures that are non-denatured and non-extracted.